17 August

986 – A Byzantine army is destroyed in the pass of Trajan's Gate by the Bulgarians under the Comitopuli Samuel and Aron. The Byzantine emperor Basil II narrowly escaped.
1807 – Robert Fulton's North River Steamboat leaves New York City for Albany, New York on the Hudson River, inaugurating the first commercial steamboat service in the world.
1862 – Indian Wars: The Dakota War of 1862 begins in Minnesota as Lakota warriors attack white settlements along the Minnesota River.
1862 – American Civil War: Major General J.E.B. Stuart is assigned command of all the cavalry of the Confederate Army of Northern Virginia.
1863 – American Civil War: In Charleston, South Carolina, Union batteries and ships bombard Confederate-held Fort Sumter.
1864 – American Civil War: Battle of Gainesville – Confederate forces defeat Union troops near Gainesville, Florida.
1883 – The first public performance of the Dominican Republic's national anthem, Himno Nacional.
1907 – Pike Place Market, a popular tourist destination and registered historic district in Seattle, opened.
1908 – Fantasmagorie, the first animated cartoon, created by Émile Cohl, is shown in Paris.
1914 – World War I: Battle of Stalluponen – The German army of General Hermann von François defeats the Russian force commanded by Pavel Rennenkampf near modern-day Nesterov, Russia.
1915 – Jewish American Leo Frank is lynched for the alleged murder of a 13-year-old girl in Marietta, Georgia, United States.
1915 – A Category 4 hurricane hits Galveston, Texas with winds at 135 miles per hour (217 km/h).
1918 – Bolshevik revolutionary leader Moisei Uritsky is assassinated.
1942 – World War II: U.S. Marines raid the Japanese-held Pacific island of Makin (Butaritari).
1943 – World War II: The U.S. Eighth Air Force suffers the loss of 60 bombers on the Schweinfurt–Regensburg mission.
1943 – World War II: The U.S. Seventh Army under General George S. Patton arrives in Messina, Italy, followed several hours later by the British 8th Army under Field Marshal Bernard L. Montgomery, thus completing the Allied conquest of Sicily.
1943 – World War II: First Québec Conference of Winston Churchill, Franklin D. Roosevelt, and William Lyon Mackenzie King begins.
1943 – World War II: The Royal Air Force begins Operation Hydra, the first air raid of the Operation Crossbow strategic bombing campaign against Germany's V-weapon programme.
1945 – Sukarno and Mohammad Hatta proclaim the independence of Indonesia, igniting the Indonesian National Revolution against the Dutch Empire.
1947 – The Radcliffe Line, the border between Union of India and Dominion of Pakistan is revealed.
1950 – Hill 303 massacre: American POWs were massacred by North Korean Army.
1953 – Addiction: First meeting of Narcotics Anonymous in Southern California.
1959 – Quake Lake is formed by the magnitude 7.5 1959 Yellowstone earthquake near Hebgen Lake in Montana.
1959 – Kind of Blue by Miles Davis, the much acclaimed and highly influential best selling jazz recording of all time, is released.
1960 – Decolonization: Gabon gains independence from France.
1962 – East German border guards kill 18-year-old Peter Fechter as he attempts to cross the Berlin Wall into West Berlin becoming one of the first victims of the wall.
1969 – Category 5 Hurricane Camille hits the Mississippi coast, killing 248 people and causing $1.5 billion in damage.
1970 – Venera Program: Venera 7 launched. It will later become the first spacecraft to successfully transmit data from the surface of another planet (Venus).
1978 – Double Eagle II becomes first balloon to cross the Atlantic Ocean when it lands in Miserey near Paris, 137 hours after leaving Presque Isle, Maine.
1979 – Two Soviet Aeroflot jetliners collide in mid-air over Ukraine, killing 156.
1980 – Azaria Chamberlain disappears, probably taken by a dingo, leading to what was then the most publicised trial in Australian history.
1982 – The first Compact Discs (CDs) are released to the public in Germany.
1988 – Pakistani President Muhammad Zia-ul-Haq and U.S. Ambassador Arnold Raphel are killed in a plane crash.
1998 – Monica Lewinsky scandal: US President Bill Clinton admits in taped testimony that he had an "improper physical relationship" with White House intern Monica Lewinsky. On the same day he admits before the nation that he "misled people" about the relationship.
1999 – A 7.4-magnitude earthquake strikes İzmit, Turkey, killing more than 17,000 and injuring 44,000.
2004 – The National Assembly of Serbia unanimously adopts new state symbols for Serbia: Boze Pravde becomes the new anthem and the coat of arms is adopted for the whole country.
2005 – The first forced evacuation of settlers, as part of the Israel unilateral disengagement plan, starts.
2005 – Over 500 bombs are set off by terrorists at 300 locations in 63 out of the 64 districts of Bangladesh
2008 – American swimmer Michael Phelps becomes the first person to win eight gold medals in one Olympic Games.
2009 – An accident at the Sayano–Shushenskaya Dam in Khakassia, Russia, kills 75 and shuts down the hydroelectric power station, leading to widespread power failure in the local area.

Holidays and observances

Christian Feast Day:
Clare of the Cross
Hyacinth of Poland
Mammes of Caesarea (Roman Catholic Church)
August 17 (Eastern Orthodox liturgics)
Independence Day, celebrates the proclamation of Indonesia's independence from Japan in 1945.
Portunalia (Roman Empire)
Prekmurje Union Day (Slovenia)
San Martin Day (Argentina)
Smile and Wave to Tourists International Day