17 July

180 – Twelve inhabitants of Scillium in North Africa are executed for being Christians. This is the earliest record of Christianity in that part of the world.
1203 – The Fourth Crusade captures Constantinople by assault. The Byzantine emperor Alexius III Angelus flees from his capital into exile.
1402 – Zhu Di, better known by his era name as the Yongle Emperor, assumes the throne over the Ming Dynasty of China.
1453 – Battle of Castillon: The last battle of Hundred Years' War, the The French under Jean Bureau defeat the English under the Earl of Shrewsbury, who is killed in the battle in Gascony.
1586 – A meeting takes place at Lüneburg between several Protestant powers in order to discuss the formation of an 'evangelical' league of defence, called the 'Confederatio Militiae Evangelicae', against the Catholic League.
1717 – King George I of Great Britain sails down the River Thames with a barge of 50 musicians, where George Frideric Handel's Water Music is premiered.
1762 – Catherine II becomes tsar of Russia upon the murder of Peter III of Russia.
1771 – Bloody Falls Massacre: Chipewyan chief Matonabbee, travelling as the guide to Samuel Hearne on his Arctic overland journey, massacres a group of unsuspecting Inuit.
1791 – Members of the French National Guard under the command of General Lafayette open fire on a crowd of radical Jacobins at the Champ de Mars, Paris, during the French Revolution, killing as many as 50 people.
1794 – The sixteen Carmelite Martyrs of Compiegne are executed 10 days prior to the end of the French Revolution's Reign of Terror.
1856 – The Great Train Wreck of 1856 in Fort Washington, Pennsylvania, kills over 60 people.
1867 – Harvard School of Dental Medicine was established in Boston. It was the first dental school in the U.S.
1899 – NEC Corporation is organized as the first Japanese joint venture with foreign capital.
1917 – King George V of the United Kingdom issues a Proclamation stating that the male line descendants of the British royal family will bear the surname Windsor.
1918 – On the orders of the Bolshevik Party carried out by Cheka, Tsar Nicholas II of Russia and his immediate family and retainers are murdered at the Ipatiev House in Ekaterinburg, Russia.
1918 – The RMS Carpathia, the ship that rescued the 705 survivors from the RMS Titanic, is sunk off Ireland by the German SM U-55; 5 lives are lost.
1932 – Altona Bloody Sunday.
1933 – After successfully crossing the Atlantic Ocean, the Lithuanian research aircraft Lituanica crashes in Europe under mysterious circumstances.
1936 – Spanish Civil War: An Armed Forces rebellion against the recently-elected leftist Popular Front government of Spain starts the civil war.
1938 – Douglas Corrigan takes off from Brooklyn to fly the "wrong way" to Ireland and becomes known as "Wrong Way" Corrigan.
1944 – Port Chicago disaster: Near the San Francisco Bay, two ships laden with ammunition for the war explode in Port Chicago, California, killing 320.
1944 – World War II: Napalm incendiary bombs are dropped for the first time by American P-38 pilots on a fuel depot at Coutances, near St. Lô, France.
1948 – The South Korean constitution is proclaimed.
1955 – Disneyland is dedicated and opened by Walt Disney in Anaheim, California.
1962 – Nuclear weapons testing: The "Small Boy" test shot Little Feller I becomes the last atmospheric test detonation at the Nevada Test Site.
1968 – A revolution occurs in Iraq when Abdul Rahman Arif is overthrown and the Ba'ath Party is installed as the governing power in Iraq with Ahmed Hassan al-Bakr as the new Iraqi President.
1973 – King Mohammed Zahir Shah of Afghanistan is deposed by his cousin Mohammed Daoud Khan while in Italy undergoing eye surgery.
1975 – Apollo-Soyuz Test Project: An American Apollo and a Soviet Soyuz spacecraft dock with each other in orbit marking the first such link-up between spacecraft from the two nations.
1976 – History of East Timor: East Timor is annexed, and becomes the 27th province of Indonesia.
1976 – The opening of the Summer Olympics in Montreal is marred by 25 African teams boycotting the New Zealand team.
1979 – Nicaraguan president General Anastasio Somoza Debayle resigns and flees to Miami, Florida.
1981 – The opening of the Humber Bridge by HM The Queen in England.
1981 – A structural failure leads to the collapse of a walkway at the Hyatt Regency in Kansas City, Missouri killing 114 people and injuring more than 200.
1989 – First flight of the B-2 Spirit Stealth Bomber.
1996 – TWA Flight 800: Off the coast of Long Island, New York, a Paris-bound TWA Boeing 747 explodes, killing all 230 on board.
1998 – Papua New Guinea earthquake: A tsunami triggered by an undersea earthquake destroys 10 villages in Papua New Guinea killing an estimated 3,183, leaving 2,000 more unaccounted for and thousands more homeless.
1998 – A diplomatic conference adopts the Rome Statute of the International Criminal Court, establishing a permanent international court to prosecute individuals for genocide, crime against humanity, war crimes, and the crime of aggression.
2007 – TAM Airlines (TAM Linhas Aéreas) Flight 3054 crashes upon landing during rain in São Paulo. This is Brazil's deadliest aviation accident to date with an estimated 199 deaths.
2009 – Jakarta double bombings at the JW Marriott and Ritz-Carlton Hotels killed 9 people including 4 foreigners.

Holidays and observances

Christian Feast Day:
Alexius of Rome (Western Church)
Cynehelm
Cynllo
Jadwiga of Poland
Martyrs of Compiègne
Magnus Felix Ennodius
Marcellina
Piatus of Tournai
Romanov sainthood (Russian Orthodox Church)
Speratus and companions
July 17 (Eastern Orthodox liturgics)
Constitution Day (South Korea)
Independence Day (Slovakia)
King's Birthday (Lesotho)
World Day for International Justice (International)
Yellow Pig's Day
Yama-boko Junkō of the Gion Matsuri (Kyoto, Japan)