September 17 in History

The 10s decade ran from January 1, AD 10, to December 31, AD 19.

The Kingdom of Galicia was a political entity located in southwestern Europe, which, at its territorial zenith, occupied the entire northwest of the Iberian Peninsula. In the early 10th century, the Kingdom of Galicia was formed following the division of the Kingdom of Asturias after the death of Alfonso III in 910. His sons split the kingdom, with Ordoño II inheriting Galicia. While Galicia became a distinct political entity, it remained closely tied to the Leonese and Asturian realms through dynastic connections. Later, Ordoño II integrated Galicia into the Kingdom of León when he inherited the latter. Though the Kingdom of Galicia had moments of semi-independence, it was typically seen as part of the Kingdom of León. Compostela became the capital of Galicia in the 11th century, while the independence of Portugal (1128) determined its southern boundary. The accession of Castilian King Ferdinand III to the Leonese kingdom in 1230 brought Galicia under the control of the Crown of Castile.

The Battle of Myriokephalon (also known as the Battle of Myriocephalum, Greek: Μάχη του Μυριοκέφαλου, Turkish: Miryokefalon Savaşı or Düzbel Muharebesi) was a battle between the Byzantine Empire and the Seljuk Turks in the mountains west of Iconium (Konya) in west-central Anatolia on 17 September 1176. The battle was a strategic reverse for the Byzantine forces, who were ambushed when moving through a mountain pass. In 1161, the Seljuk Sultan of Rum Kilij Arslan II and Byzantine Emperor Manuel I Komnenos concluded a peace agreement. Manuel wanted to achieve peace for his Anatolian provinces with the help of this treaty. Kilij Arslan needed to eliminate internal rivals and gather his strength. After the death of Nureddin Zangi in 1174, the Sultan conquered the Danishmend emirates and expelled his brother Shahinshah, the ruler of Ankara. The emirs fled to Manuel, who demanded the surrender of the captured territories of the Danishmendids to him, which the Sultan was obliged to do under the treaty. However, Kilij Arslan ignored Manuel's request. In 1176, Manuel I Komnenos gathered a large army and set out on a campaign against Konya. The Seljuks, under the command of Kilij Arslan II, organised an ambush at the Tzivritze Pass and defeated the Byzantine Army. According to the Byzantine historian Niketas Choniates, in the vicinity of the pass there were the ruins of the fortress named Myriokephalon, which gave the name to the battle. The exact location of the battle is the subject of debate among researchers. The battle was to be the final, unsuccessful effort by the Byzantines to recover the interior of Anatolia from the Seljuk Turks.

Louis I of Hungary, also known as Louis the Great (Hungarian: Nagy Lajos; Croatian: Ludovik Veliki; Slovak: Ľudovít Veľký) or Louis the Hungarian (Polish: Ludwik Węgierski, Italian: Luigi l'ungherese; 5 March 1326 – 10 September 1382), was King of Hungary and Croatia from 1342 and King of Poland from 1370 until his death in 1382. He was the first child of Charles I of Hungary and his wife, Elizabeth of Poland, to survive infancy. A 1338 treaty between his father and Casimir III of Poland, Louis's maternal uncle, confirmed Louis's right to inherit the Kingdom of Poland if his uncle died without a son. In exchange, Louis was obliged to assist his uncle in reoccupying the lands that Poland had lost in previous decades. He bore the title Duke of Transylvania between 1339 and 1342 but did not administer the province. Louis was of age when he succeeded his father in 1342, but his deeply religious mother exerted a powerful influence on him. He inherited a centralised kingdom and a rich treasury from his father. During the first years of his reign, Louis launched a crusade against the Lithuanians and restored royal power in Croatia; his troops defeated a Tatar army, expanding his authority towards the Black Sea. When his brother, Andrew, Duke of Calabria, husband of Queen Joanna I of Naples, was assassinated in 1345, Louis accused the queen of his murder and punishing her became the principal goal of his foreign policy. He launched two campaigns to the Kingdom of Naples between 1347 and 1350. His troops occupied large territories on both occasions, and Louis adopted the styles of Neapolitan sovereigns (including the title of King of Sicily and Jerusalem), but the Holy See never recognised his claim. Louis's arbitrary acts and atrocities committed by his mercenaries made his rule unpopular in Southern Italy. He withdrew all his troops from the Kingdom of Naples in 1351. Like his father, Louis administered Hungary with absolute power and used royal prerogatives to grant privileges to his courtiers. However, he also confirmed the liberties of the Hungarian nobility at the Diet of 1351, emphasising the equal status of all noblemen. At the same Diet, he introduced an entail system and a uniform rent payable by the peasants to the landowners, and confirmed the right to free movement for all peasants. He waged wars against the Lithuanians, Serbia, and the Golden Horde in the 1350s, restoring the authority of Hungarian monarchs over territories along frontiers that had been lost during previous decades. He forced the Republic of Venice to renounce the Dalmatian towns in 1358. He also made several attempts to expand his suzerainty over the rulers of Bosnia, Moldavia, Wallachia, and parts of Bulgaria and Serbia. These rulers were sometimes willing to yield to him, either under duress or in the hope of support against their internal opponents, but Louis's rule in these regions was only nominal during most of his reign. His attempts to convert his pagan or Orthodox subjects to Catholicism made him unpopular in the Balkan states. Louis established a university in Pécs in 1367, but it was closed within two decades because he did not arrange for sufficient revenues to maintain it. Louis inherited Poland after his uncle's death in 1370. Since he had no sons, he wanted his subjects to acknowledge the right of his daughters to succeed him in both Hungary and Poland. For this purpose, he issued the Privilege of Koszyce (now Košice in Slovakia) in 1374, spelling out the liberties of Polish noblemen. However, his rule remained unpopular in Poland. In Hungary, he authorised the royal free cities to delegate jurors to the high court, hearing their cases and set up a new high court. Suffering from a skin disease, Louis became even more religious during the last years of his life. At the beginning of the Western Schism, he acknowledged Urban VI as the legitimate pope. After Urban deposed Joanna and put Louis's relative Charles of Durazzo on the throne of Naples, Louis helped Charles occupy the kingdom. In Hungarian historiography, Louis was regarded for centuries as the most powerful Hungarian monarch who ruled over an empire "whose shores were washed by three seas".

Manuel II Palaiologos or Palaeologus was Byzantine emperor from 1391 to 1425. Shortly before his death he was tonsured a monk and received the name Matthaios (Ματθαίος). Manuel was a vassal of the Ottoman Empire, which sometimes threatened to capture his territory outright. Accordingly he continued his father's practice of soliciting Western European aid against the Ottomans, and personally visited several foreign courts to plead his cause. These efforts failed, although an Ottoman civil war and Byzantine victories against Latin neighbors helped Manuel's government survive and slightly expand its influence. His wife Helena Dragaš saw to it that their sons, John VIII and Constantine XI, became emperors. He is commemorated by the Greek Orthodox Church on 21 July.

The Thirteen Years' War, also called the War of the Cities, was a conflict fought in 1454–1466 between the Prussian Confederation, allied with the Crown of the Kingdom of Poland, and the State of the Teutonic Order.

Finnish is a Finnic language of the Uralic language family, spoken by the majority of the population in Finland and by ethnic Finns outside of Finland. Finnish is one of the two official languages of Finland, alongside Swedish. In Sweden, both Finnish and Meänkieli are official minority languages. Kven, which like Meänkieli is mutually intelligible with Finnish, is spoken in the Norwegian counties of Troms and Finnmark by a minority of Finnish descent. However, these are recognized as independent languages in their relative countries for sociohistorical reasons.

The Polish–Ottoman War (1620–1621) was a conflict between the Polish–Lithuanian Commonwealth and the Ottoman Empire over the control of Moldavia. It ended with the Commonwealth withdrawing its claims on Moldavia and led to the eventual demise of the Sultan Osman II. It is also known as the Khotyn War, because it was ended by the Treaty of Khotyn (9 October 1621) in the aftermath of the final Battle of Khotyn (1621).

Boston is the capital and most populous city of the U.S. state of Massachusetts. It serves as a cultural and financial center of New England, a region of the Northeastern United States. Boston has an area of 48.4 square miles (125 km2) and a population of 675,647 as of the 2020 census, making it the third-most populous city in the Northeastern United States after New York City and Philadelphia. The larger Greater Boston metropolitan statistical area had a population of 5 million in 2025, making it the largest metropolis in New England and the eleventh-largest in the United States.

The Battle of Breitenfeld, 17 September 1631, took place during the Thirty Years' War outside Breitenfeld, Leipzig, in modern Saxony. In one of the most significant battles of the war, a combined Swedish-Saxon force defeated an army made up of Imperial and Catholic League troops. Swedish intervention in the Thirty Years' War began in June 1630 when nearly 18,000 soldiers under Gustavus Adolphus landed in Pomerania. He made an alliance with John George I, Elector of Saxony, prompting an invasion of Saxony in early 1631 by Imperial troops led by Johann Tserclaes, Count of Tilly. The combined Swedish-Saxon force marched on Leipzig where Tilly was based. At the start of the battle, the Saxon troops were routed by Tilly's cavalry, which then combined with his infantry in an attempt to envelop the Swedish army. The Swedes regrouped and launched a series of counterattacks, forcing Tilly to retreat with substantial losses. Victory allowed the Swedes to launch a campaign into southern Germany.

Antonie Philips van Leeuwenhoek was a Dutch microbiologist and microscopist in the Golden Age of Dutch art, science and technology. A largely self-taught man in science, he is commonly known as "the Father of Microbiology", and one of the first microscopists and microbiologists. Van Leeuwenhoek is best known for his pioneering work in microscopy and for his contributions toward the establishment of microbiology as a scientific discipline.

The American Revolutionary War (April 19, 1775 – September 3, 1783), also known as the Revolutionary War or American War of Independence or simply the American Revolution, was the armed conflict that comprised the final eight years of the broader American Revolution, in which American Patriot forces organized as the Continental Army and, commanded by George Washington, defeated the British Army. The conflict was fought in North America, the Caribbean, and the Atlantic Ocean. The war's outcome seemed uncertain for most of the war, but Washington and the Continental Army's decisive victory in the Siege of Yorktown in 1781 led King George III and the Kingdom of Great Britain to negotiate an end to the war. In 1783, in the Treaty of Paris, the British monarchy acknowledged the independence of the Thirteen Colonies, leading to the establishment of the United States as an independent and sovereign nation. In 1763, after the British Empire gained dominance in North America following its victory over the French in the Seven Years' War, tensions and disputes began escalating between the British and the Thirteen Colonies, especially following passage of the Stamp and Townshend Acts. The British Army responded by seeking to occupy Boston militarily, leading to the Boston Massacre on March 5, 1770. In mid-1774, with tensions escalating even further between the British Army and the colonies, the British Parliament imposed the Intolerable Acts, an attempt to disarm Americans, leading to the Battles of Lexington and Concord in April 1775, the first battles of the Revolutionary War. In June 1775, the Second Continental Congress voted to incorporate colonial-based Patriot militias into a central military, the Continental Army, and unanimously appointed Washington its commander-in-chief. Two months later, in August 1775, George III declared the colonies to be in a state of rebellion. In July 1776, the Second Continental Congress formalized the war, passing the Lee Resolution on July 2, and, two days later, unanimously adopting the Declaration of Independence, on July 4. In March 1776, in an early win for the newly-formed Continental Army under Washington's command, following a successful siege of Boston, the Continental Army successfully drove the British Army out of Boston. British commander in chief William Howe responded by launching the New York and New Jersey campaign, which resulted in Howe's capture of New York City in November. Washington responded by clandestinely crossing the Delaware River and winning small but significant victories at Trenton and Princeton. In the summer of 1777, as Howe was poised to capture Philadelphia, the Continental Congress fled to Baltimore. In October 1777, a separate northern British force under the command of John Burgoyne was forced to surrender at Saratoga in an American victory that proved crucial in convincing France and Spain that an independent United States was a viable possibility. France signed a commercial agreement with the revolutionaries, followed by a Treaty of Alliance in February 1778. In 1779, the Sullivan Expedition undertook a scorched earth campaign against British-allied factions of the Haudenosaunee Confederacy (also Iroquois). Native American raids on the American frontier, however, continued to be a problem. Also, in 1779, Spain allied with France against Great Britain in the Treaty of Aranjuez, though Spain did not formally ally with the Americans. Howe's replacement Henry Clinton intended to take the war against the Americans into the Southern Colonies. Despite some initial success, British General Cornwallis was besieged by a Franco-American army in Yorktown, Virginia, in September and October 1781. The French navy cut off Cornwallis's escape and he was forced to surrender in October. The British wars with France and Spain continued for another two years, but fighting largely ceased in North America. In the Treaty of Paris, signed on September 3, 1783, Great Britain acknowledged the sovereignty and independence of the United States, bringing the American Revolutionary War to an end. The Treaties of Versailles resolved Great Britain's conflicts with France and Spain, and forced Great Britain to cede Tobago, Senegal, and small territories in India to France, and Menorca, West Florida, and East Florida to Spain.

The Presidio of San Francisco (originally, El Presidio Real de San Francisco or The Royal Fortress of Saint Francis) is a park and former U.S. Army post on the northern tip of the San Francisco Peninsula in San Francisco, California, and is part of the Golden Gate National Recreation Area. It had been a fortified location since September 17, 1776, when New Spain established the presidio to gain a foothold in Alta California and the San Francisco Bay. It passed to Mexico in 1820, which in turn passed it to the United States in 1848. As part of a military reduction program under the Base Realignment and Closure (BRAC) process from 1988, Congress voted to end the Presidio's status as an active military installation of the U.S. Army. On October 1, 1994, it was transferred to the National Park Service, ending 219 years of military use and beginning its next phase of mixed commercial and public use. In 1996, the United States Congress created the Presidio Trust to oversee and manage the interior 80% of the park's lands, with the National Park Service managing the coastal 20%. In a first-of-its-kind structure, Congress mandated that the Presidio Trust make the Presidio financially self-sufficient by 2013. The Presidio achieved the goal in 2005, eight years ahead of the deadline. The Presidio is at the southern end of the Golden Gate Bridge, and is crossed by the bridge approach road. The park has many wooded areas, hills, and scenic vistas overlooking the Golden Gate itself, the Bridge, San Francisco Bay, and the Pacific Ocean. It was recognized as a California Historical Landmark in 1933 and as a National Historic Landmark in 1962.

The Treaty of Fort Pitt, also known as the Treaty With the Delawares, the Delaware Treaty, or the Fourth Treaty of Pittsburgh, was signed on September 17, 1778; it was the first formal treaty between the new United States of America and any Native American groups, in this case the Lenape, called the Delaware by white settlers. Although there were informal agreements between Native Americans and the Americans during the American Revolutionary War, the first one that resulted in a formal document was signed at Fort Pitt, Pennsylvania, now the site of Downtown Pittsburgh. It was essentially a treaty of military alliance between the Lenape Nation and the United States.

The Constitution of the United States is the supreme law of the United States of America. It superseded the Articles of Confederation, the nation's first constitution, on March 4, 1789. Originally including seven articles, the Constitution defined the foundational structure of the federal government.

The War of the Pyrenees, also known as War of Roussillon or War of the Convention, was the Pyrenean front of the First Coalition's war against the First French Republic. It pitted Revolutionary France against the kingdoms of Spain and Portugal from March 1793 to July 1795 during the French Revolutionary Wars. The war was fought in the eastern and western Pyrenees, at the French port of Toulon, and at sea. In 1793, a Spanish army invaded Roussillon in the eastern Pyrenees and maintained itself on French soil through April 1794. The French Revolutionary Army drove the Spanish Army back into Catalonia and inflicted a serious defeat in November 1794. After February 1795, the war in the eastern Pyrenees became a stalemate. In the western Pyrenees, the French began to win in 1794. By 1795, the French army controlled a portion of northeast Spain. The war was brutal in at least two ways. The Committee of Public Safety decreed that all French royalist prisoners be executed. Also, French generals who lost battles or otherwise displeased the representatives-on-mission often faced prison or execution. Commanders of the Army of the Eastern Pyrenees were especially unlucky in this regard.

The Low Countries theatre of the War of the First Coalition, also known as the Flanders campaign, was a series of campaigns in the Low Countries conducted from 20 April 1792 to 7 June 1795 during the first years of the War of the First Coalition. As the French Revolution radicalised, the revolutionary National Convention and its predecessors broke the Catholic Church's power (1790), abolished the monarchy (1792) and even executed the deposed king Louis XVI (1793), vying to spread the Revolution beyond the new French Republic's borders, by violent means if necessary. The First Coalition, an alliance of reactionary states representing the Ancien Régime in Central and Western Europe – Habsburg Austria, Prussia, Great Britain, the Dutch Republic, Hanover and Hesse-Kassel – mobilised military forces along all the French frontiers, threatening to invade Revolutionary France and violently restore the monarchy. The subsequent combat operations along the French borders with the Low Countries and Germany became the primary theatre of the War of the First Coalition until March 1796, when Napoleon took over French command on the Italian front.

The Finnish War was fought between the Kingdom of Sweden and the Russian Empire from 21 February 1808 to 17 September 1809 as part of the Napoleonic Wars. As a result of the war, the eastern third of Sweden was established as the autonomous Grand Duchy of Finland within the Russian Empire. Other notable effects were the Swedish parliament's adoption of a new constitution and the establishment of the House of Bernadotte, the new Swedish royal house, in 1818.

Joshua Abraham Norton (February 4, 1818 – January 8, 1880), commonly known as Emperor Norton, was a resident of San Francisco, California, who declared himself Emperor of the United States in 1859 and Protector of Mexico in 1866, roles that he maintained until his death in 1880. Norton's notable acts include proposing the construction of what opened as the San Francisco–Oakland Bay Bridge in 1936. Born in England and raised in South Africa, Norton left Cape Town in late 1845, sailing from Liverpool to Boston in early 1846 and eventually arriving in San Francisco in late 1849. After a brief period of prosperity, Norton made a business gambit in late 1852 that played out poorly, ultimately forcing him to declare bankruptcy in 1856. Norton proclaimed himself "Emperor of these United States" in a proclamation that he signed "Norton I., Emperor of the United States." He justified his reign by citing a need for political stability shortly before the American Civil War (1861-1865). Norton took the secondary title "Protector of Mexico" in 1866 as a sign of his opposition towards the French intervention in Mexico (1863-1867). Norton had no formal political power yet acted as emperor for the rest of his life, and was treated deferentially in San Francisco and elsewhere in California. He issued currency in his name that was honored in some of the establishments he frequented. San Francisco merchants capitalized on Norton's notoriety by selling souvenirs bearing his image. Norton received free ferry and train passage and a variety of favors, such as help with rent and free meals, from well-placed friends and sympathizers. Some considered Norton to be insane or eccentric, but residents of San Francisco and the city's larger Northern California orbit enjoyed his imperial presence and took note of his frequent newspaper proclamations. Norton was the basis for characters created by Mark Twain, Robert Louis Stevenson, Christopher Moore, Morris and René Goscinny, Selma Lagerlöf, Neil Gaiman, Mircea Cărtărescu, and Charles Bukowski. Norton and his proposal for the Bay Bridge were featured on an episode of Bonanza.

The Argentine Civil Wars were a series of civil conflicts of varying intensity that took place from 1814 to 1853 in the territories of Argentina. Beginning concurrently with the Argentine War of Independence, the conflicts prevented the formation of a stable governing body until the signing of the Argentine Constitution of 1853, followed by low-frequency skirmishes that ended with the Federalization of Buenos Aires in 1880.

The American Civil War was a civil war in the United States between the Union and the Confederacy, which was formed in 1861 by states that had seceded from the Union to preserve slavery in the United States. The South saw slavery as threatened because of the election of Abraham Lincoln and the growing abolitionist movement in the North. The war ended with Union victory, the dissolution of the Confederacy and the abolition of slavery, freeing four million African Americans.

The Allegheny Arsenal, established in 1814, was an important supply and manufacturing center for the Union Army during the American Civil War, and the site of the single largest civilian disaster during the war. It was located in the community of Lawrenceville, Pennsylvania, which was annexed by the city of Pittsburgh in 1868.

The Battle of the Yalu River (simplified Chinese: 黄海海战; traditional Chinese: 黃海海戰; pinyin: Huáng Hǎi Hǎizhàn; Japanese: 黄海海戦, romanized: Kōkai-kaisen; lit. 'Naval Battle of the Yellow Sea') was the largest naval engagement of the First Sino-Japanese War, and took place on 17 September 1894, the day after the Japanese victory at the land Battle of Pyongyang. The Imperial Japanese Navy defeated the Chinese Beiyang Fleet. The battle is also known by a variety of other names: Battle of Haiyang Island, Battle of Dadonggou, Battle of the Yellow Sea and Battle of Yalu, after the location of the battle, which was in the Yellow Sea off the mouth of the Yalu River, not in the river itself. There is no agreement among contemporary sources on the exact numbers and composition of each fleet, but they were of a similar size, and the battle is considered to be one of the Imperial Japanese Navy's greatest victories.

The Philippine–American War, known alternatively as the Filipino–American War, Philippine Insurrection, or Tagalog Insurgency, emerged in early 1899 following the United States' annexation of the former Spanish colony of the Philippine Islands under the terms of the December 1898 Treaty of Paris following the Spanish–American War. Philippine nationalists had proclaimed independence in June 1898 and constituted the First Philippine Republic in January 1899. The United States did not recognize either event as legitimate, and tensions escalated until fighting commenced on February 4, 1899, in the Battle of Manila.

The Second Boer War was a conflict fought between 1899 and 1902 between the British Empire and the Boer republics, triggered by the discovery of gold in the Transvaal, specifically the Witwatersrand gold fields, and the ensuing political dispute over the voting rights of British expatriates (Uitlanders).

The Battle of Elands River took place near the Elands River Poort mountain pass on 17 September 1901 during the Second Boer War. During the battle a Boer raiding force under Jan Smuts destroyed a British cavalry squadron led by Captain Sandeman, a cousin of Winston Churchill, on the Modderfontein farm. This battle is therefore also known as the Battle of Modderfontein.

The Wright Flyer made the first sustained flight by a manned heavier-than-air powered and controlled aircraft on December 17, 1903. Invented and flown by brothers Orville and Wilbur Wright, it marked the beginning of the pioneer era of aviation.

Andrew Fisher (29 August 1862 – 22 October 1928) was the fifth prime minister of Australia from 1908 to 1909, from 1910 to 1913 and from 1914 to 1915. He held office as the leader of the Australian Labor Party (ALP), and was particularly notable for leading the party to its first federal election victory and first majority government at the 1910 federal election. Fisher was born in Crosshouse, Ayrshire, Scotland. He left school at a young age to work in the nearby coal mines, becoming secretary of the local branch of the Ayrshire Miners' Union at the age of 17. Fisher emigrated to Australia in 1885, where he continued his involvement with trade unionism. He settled in Gympie, Queensland, and in 1893 was elected to the Queensland Legislative Assembly as a representative of the Labor Party. Fisher lost his seat in 1896, but returned in 1899 and later that year briefly was a minister in the government of Anderson Dawson. In 1901, Fisher was elected to the new federal parliament representing the Division of Wide Bay. He was the Minister for Trade and Customs for a few months in 1904, in the short-lived government of Chris Watson. Fisher was elected deputy leader of the ALP in 1905 and replaced Watson as leader in 1907. He initially provided support to the minority government of Protectionist leader Alfred Deakin, but in November 1908 the ALP withdrew its support and Deakin resigned as prime minister. Fisher subsequently formed a minority government of his own. It lasted only a few months, as in June 1909 Deakin returned as prime minister at the head of a new anti-socialist Liberal Party. Fisher returned as prime minister after the 1910 federal election, which saw Labor attain majority government for the first time in its history. His second government passed wide-ranging reforms – old-age and disability pensions, enshrined new workers' rights in legislation, established the Commonwealth Bank, oversaw the continued expansion of the Royal Australian Navy, began construction on the Trans-Australian Railway, and formally established what is now the Australian Capital Territory. However, at the 1913 election the ALP narrowly lost its House of Representatives majority to the Liberal Party, with Fisher being replaced as prime minister by Joseph Cook. After just over a year in office, Cook was forced to call a new election, the first double dissolution. Labor won back its majority in the House, and Fisher returned for a third term as prime minister. During the election campaign he famously declared that Australia would defend Britain "to the last man and the last shilling". However, he struggled with the demands of Australia's participation in World War I and in October 1915 resigned in favour of his deputy Billy Hughes. Fisher subsequently accepted an appointment as the High Commissioner of Australia to the United Kingdom, holding the position from 1916 to 1920. After a brief return to Australia, he retired to London, dying there at the age of 66. His cumulative total of just under five years as prime minister is the second-longest by an ALP leader, surpassed only by Bob Hawke.

World War I, or the First World War, also known as the Great War, was a global conflict between two coalitions: the Allies and the Central Powers. One of the deadliest conflicts in history, World War I resulted in an estimated 15 to 22 million deaths, including those in war crimes and genocides. The war also helped spread the Spanish flu pandemic. The conflict saw important developments in weaponry, including the first large-scale use of machine guns, artillery, aircraft, chemical weapons, and tanks.

Rittmeister Manfred Albrecht Freiherr von Richthofen, known in English as Baron von Richthofen or the Red Baron, was a German fighter pilot with the German Air Force during World War I. He is considered the ace-of-aces of the war, being officially credited with 80 air combat victories.

The National Football League (NFL) is a professional American football league in the United States. Composed of 32 teams, it is divided equally between the American Football Conference (AFC) and the National Football Conference (NFC). The NFL is one of the major professional sports leagues in the United States and Canada and the highest professional level of American football in the world. Each NFL season begins annually with a three-week preseason in August, followed by an 18-week regular season, which runs from early September to early January, with each team playing 17 games and having one bye week. Seven teams from each conference, including the four division winners and three wild card teams, then advance to the playoffs, a single-elimination tournament, which culminates in the Super Bowl, played in early February between the winners of the AFC and NFC championship games. The NFL is headquartered in New York City.

The Border Protection Corps was a military formation of the Second Polish Republic that was created in 1924 to defend the country's eastern borders against armed Soviet incursions and local bandits. Other borders were under the jurisdiction of a separate, regular Border Guard state security agency.

The Okeechobee hurricane of 1928, also known as the San Felipe Segundo hurricane and Florida's Forgotten Storm, was one of the deadliest hurricanes in the recorded history of the North Atlantic basin, and the fourth deadliest hurricane in the United States, only behind the 1900 Galveston hurricane, 1899 San Ciriaco hurricane, and Hurricane Maria in 2017.

The Ararat rebellion, also known as the Ağrı rebellion, was a 1930 uprising by the Kurds of Ağrı Province, in eastern Turkey, against the Turkish government. The leader of the guerrilla forces during the rebellion was Ihsan Nuri of the Jibran branch of the Jalali tribe.

Laureano Eleuterio Gómez Castro was a Colombian politician and civil engineer who served as President of Colombia from 1950 to 1953. In November 1951 poor health led him to cede presidential power to Roberto Urdaneta Arbeláez. On 13 June 1953, when he tried to resume his presidency, he was overthrown in a military coup led by Gustavo Rojas Pinilla.

The Niagara Gorge Railroad was an interurban railway which ran at the bottom of the Niagara Gorge from Niagara Falls, New York to Lewiston, New York.

World War II, or the Second World War, was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all of the world's countries participated, with many engaging in total war on an unprecedented scale. World War II was the deadliest conflict in history, causing the deaths of 60 to 75 million people, a majority of whom were civilians. Millions died as a result of massacres, starvation, disease, and genocides including the Holocaust. After the Allied victory, Germany, Austria, Japan, and Korea were occupied, and German and Japanese leaders were tried for war crimes.

German submarine U-29 was a Type VIIA U-boat of Nazi Germany's Kriegsmarine during World War II.

The Battle of Britain was a military campaign of the Second World War, in which the Royal Air Force (RAF) and the Fleet Air Arm (FAA) of the Royal Navy defended the United Kingdom against large-scale attacks by Nazi Germany's air force, the Luftwaffe. It was the first major military campaign fought entirely by air forces. It takes its name from the speech given by Prime Minister Winston Churchill to the House of Commons on 18 June 1940: "What General Weygand called the 'Battle of France' is over. I expect that the Battle of Britain is about to begin."

Vsevobuch, a portmanteau for "Universal Military Training", was a system of compulsory military training for men practiced in the Russian SFSR governed by the Chief Administration of Universal Military Training of the People's Commissariat of Military Affairs.

The Anglo-Soviet invasion of Iran, also known as the Anglo-Soviet invasion of Persia or the Allied invasion of Iran, was the joint invasion of the officially neutral Imperial State of Iran by the United Kingdom and the Soviet Union in August 1941. The two powers announced that they would stay until six months after the end of the war with their mutual enemy, Nazi Germany, which turned out to be 2 March 1946. On that date the British began to withdraw, while the Soviet Union delayed until May, initially citing "threats to Soviet security", followed by the Iran crisis of 1946.

Operation Market Garden was an Allied military operation during the Second World War, fought in the German-occupied Netherlands from 17 to 25 September 1944. Its objective was to create a salient spanning 62 miles (100 km) into German territory with a bridgehead over the Nederrijn, creating an Allied invasion route into northern Germany. This was to be achieved by two sub-operations: seizing nine bridges with combined American, British and Polish airborne forces ("Market") followed by British land forces swiftly following over the bridges ("Garden").

The Tallinn offensive was a strategic offensive by the Red Army's 2nd Shock Army and 8th Army and the Baltic Fleet against the German Army Detachment Narwa and Estonian units in mainland Estonia on the Eastern Front of World War II on 17–26 September 1944. Its German counterpart was the abandonment of the Estonian territory in a retreat codenamed Operation Aster.

The Battle of San Marino was an engagement on 17–20 September 1944 during the Italian Campaign of the Second World War, in which German Army forces occupied the neutral Republic of San Marino microstate and were then attacked by Allied forces. It is also sometimes known as the Battle of Monte Pulito.

Lehi, officially the Fighters for the Freedom of Israel and often known pejoratively as the Stern Gang, was a Zionist paramilitary militant organization founded by Avraham ("Yair") Stern in Mandatory Palestine in 1940. Its avowed aim was to evict the British authorities from Palestine by use of violence, allowing unrestricted immigration of Jews and the formation of a Jewish state. It was initially called the National Military Organization in Israel, upon being founded in August 1940, and considered its actions as necessary for achieving its national aims.

Nizam of Hyderabad was the title of the ruler of Hyderabad State. Nizam is a shortened form of Niẓām ul-Mulk, and was the title bestowed upon Asaf Jah I when he was appointed Viceroy of the Deccan by the Mughal emperor Farrukhsiyar. In addition to being the Mughal viceroy (Naib) of the Deccan, Asaf Jah I was also the premier courtier of the Mughal Empire until 1724, when he established an independent realm based in Hyderabad, but in practice, continued to recognise the nominal authority of the emperor.

SS Noronic was a Canadian passenger ship that was destroyed by fire in Toronto Harbour in September 1949 with the loss of at least 118 lives.

The People's Liberation Army Air Force Airborne Corps is a corps grade airborne and air assault force subordinated to People's Liberation Army Air Force (PLAAF) headquarters. Before April 2017, the Airborne Corps was called the PLAAF 15th Airborne Corps.

India, officially the Republic of India, is a country in South Asia. It is the world's seventh-largest country by area and the largest by population. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the north; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is near Sri Lanka and the Maldives.

The Civic Arena, formerly the Civic Auditorium and later Mellon Arena, was a multi-purpose arena located in Downtown Pittsburgh, Pennsylvania. It primarily served as the home to the Pittsburgh Penguins, the city's National Hockey League (NHL) franchise, from 1967 to 2010.

Northwest Orient Airlines Flight 706 was a Lockheed L-188 Electra aircraft, registration N137US, which crashed on take-off from Chicago's O'Hare International Airport September 17, 1961. All 37 on board were killed in the accident.

The Battle of Chawinda was a major engagement between Pakistan and India during the Indo-Pakistani war of 1965 as part of the Sialkot campaign. It is well known as being one of the largest tank battles in history since the Battle of Kursk, which was fought between the Soviet Union and Nazi Germany in World War II.

Bangladesh, officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world with a population of almost 177.8 million people within an area of 148,461 square kilometres (57,321 sq mi). Bangladesh shares land borders with India to the north, west, and east, and Myanmar to the southeast. It has a coastline along the Bay of Bengal to its south and is separated from Bhutan and Nepal by the Siliguri Corridor, and from China by the Indian states of West Bengal and Sikkim to its north. Dhaka, the capital and largest city, is the nation's political, financial, and cultural centre. Chittagong is the second-largest city and the busiest port of the country.

Space Shuttle Enterprise is the first orbiter of the Space Shuttle system. Rolled out on September 17, 1976, it was built for NASA as part of the Space Shuttle program to perform atmospheric test flights after being launched from a modified Boeing 747. It was constructed without engines or a functional heat shield. As a result, it was not capable of spaceflight.

The Camp David Accords were a pair of political agreements signed by Egyptian president Anwar Sadat and Israeli prime minister Menachem Begin on 17 September 1978, following twelve days of secret negotiations at Camp David, the country retreat of the president of the United States in Maryland. The two framework agreements were signed at the White House and were witnessed by President Jimmy Carter. The second of these frameworks led directly to the 1979 Egypt–Israel peace treaty. Due to the agreement, Sadat and Begin received the shared 1978 Nobel Peace Prize. The first framework, which dealt with the Palestinian territories, was written without participation of any Palestinians and was condemned by the United Nations.

The Gdańsk Shipyard is a large Polish shipyard, located in the city of Gdańsk, northern Poland. The yard gained international fame when Polish trade union Solidarity was founded there in September 1980. It is situated on the western side of Martwa Wisła and on Ostrów Island.

Anastasio "Tachito" Somoza Debayle was a Nicaraguan politician, military officer, hydraulic engineer, and dictator who served as the 53rd President of Nicaragua from 1967 to 1972 and again from 1974 until his fall in 1979. As head of the National Guard, he was de facto ruler of the country between 1967 and 1979, even during the period when he was not the de jure ruler.

Vanessa Lynn Williams is an American singer, actress, model, producer and dancer. She gained recognition as the first Black woman to win the Miss America title when she was crowned Miss America 1984. She would later resign her title amid a media controversy surrounding nude photographs published in Penthouse magazine. Thirty-two years later, Williams was offered a public apology during the Miss America 2016 pageant for the events.

Estonia, officially the Republic of Estonia, is a country in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the Baltic Sea across from Sweden, to the south by Latvia, and to the east by Russia. The territory of Estonia consists of the mainland, the larger islands of Saaremaa and Hiiumaa, and over 2,300 other islands and islets on the east coast of the Baltic Sea. Its capital city of Tallinn, along with the city of Tartu, are the country's two largest urban areas. The Estonian language, of the Finnic family, is the official language and the first language of the majority of nearly 1.4 million people. Estonia is one of the least populous member states of the European Union.

Linux is a family of free and open-source software Unix-like operating systems based on the Linux kernel, which was first released on 17 September 1991 by Linus Torvalds. Some members of the family are typically packaged as a distribution, which includes the kernel alongside supporting system software and libraries developed by third parties—such as GNU, Red Hat, and X.Org—to create a complete operating system; however, not all Linux-based operating systems are considered distros, with Android being an example. Linux was originally designed as a clone of Unix and is distributed under the copyleft GPL license.

In the Mykonos restaurant assassinations, Iranian-Kurdish opposition leaders Sadegh Sharafkandi, Fattah Abdoli, Homayoun Ardalan and their translator Nouri Dehkordi, were assassinated at the Mykonos Greek restaurant in Berlin, Germany on 17 September 1992. The assassination took place during the KDPI insurgency (1989–96), as part of the general Kurdish separatism in Iran. The assassins were believed by German courts to have links to Iranian intelligence. Kazem Darabi, an Iranian intelligence service employee, was tried and sentenced to life imprisonment by the Berlin Supreme Court.

The New York Stock Exchange is an American stock exchange headquartered at the New York Stock Exchange Building in the Financial District of Lower Manhattan in New York City. It is the largest stock exchange in the world by market capitalization, exceeding in January 2026. The NYSE is owned by Intercontinental Exchange, an American holding company that it also lists. Previously, it was part of NYSE Euronext (NYX), which was formed by the NYSE's 2007 merger with Euronext.

George Walker Bush is an American former politician, businessman, and Air Force veteran who served as the 43rd president of the United States from 2001 to 2009. A member of the Republican Party, he served as the 46th governor of Texas from 1995 to 2000. He is the eldest son of George H. W. Bush, the 41st president of the United States.

Fourpeaked Mountain, also known as Fourpeaked Volcano, is an active stratovolcano located in the U.S. state of Alaska within Katmai National Park and Preserve. The volcano is nearly completely covered by Fourpeaked Glacier.

The Őszöd speech was a speech Hungarian Prime Minister Ferenc Gyurcsány delivered to the 2006 Hungarian Socialist Party (MSZP) congress in Balatonőszöd. Though the May congress was confidential, Gyurcsány's address was leaked and broadcast by Magyar Rádió on Sunday, 17 September 2006, igniting a nationwide political crisis.

Occupy Wall Street (O.W.S.) was a left-wing populist and progressive movement against economic inequality, capitalism, corporate greed, big finance, and the influence of money in politics. It began in Zuccotti Park, located in New York City's Financial District, and lasted for fifty-nine days—from September 17 to November 15, 2011.

Grand Theft Auto V is a 2013 action-adventure game developed by Rockstar North and published by Rockstar Games. It is the seventh main entry in the Grand Theft Auto series, following 2008's Grand Theft Auto IV, and the fifteenth instalment overall. Set within the fictional state of San Andreas, based on Southern California, the single-player story follows three protagonists—retired bank robber Michael De Santa, street gangster Franklin Clinton, and drug dealer and gunrunner Trevor Philips —and their attempts to commit heists while under pressure from a corrupt government agency and powerful criminals. Players freely roam San Andreas's open-world countryside and fictional city of Los Santos, based on Los Angeles.

On September 17–19, 2016, a series of three constructed bombs exploded, and several unexploded devices were discovered in the New York metropolitan area followed by a subsequent shooting in Linden, New Jersey during a nationwide manhunt to locate the suspected bomber. The bombings and additional police shootout with the perpetrator left 33 people wounded, but no fatalities were reported. Federal and local investigators determined these explosive devices were deliberately set and identified them as part of a terrorist act.

The Strategic Mutual Defence Agreement (SMDA) is a security and defence pact between the countries of Pakistan and Saudi Arabia. Under this agreement both countries have committed to treating any act of aggression against one as an act against both known as collective security.