• 636 - Battle of Yarmouk: Arab forces led by Khalid ibn al-Walid take control of Syria and Palestine away from the Byzantine Empire, marking the first great wave of Muslim conquests and the rapid advance of Islam outside Arabia.
• 917 - Battle of Anchialus: Tsar Simeon I of Bulgaria invades Thrace and drives the Byzantines out.
• 1000 - The foundation of the Hungarian state, Hungary is established as a Christian kingdom by Stephen I of Hungary.
• 1391 - Konrad von Wallenrode becomes the 24th Hochmeister of the Teutonic Order.
• 1672 - Former Grand Pensionary Johan de Witt and his brother Cornelis were brutally murdered by an angry mob in The Hague.
• 1794 - Battle of Fallen Timbers - American troops force a confederacy of Shawnee, Mingo, Delaware, Wyandot, Miami, Ottawa, Chippewa, and Potawatomi warriors into a disorganized retreat.
• 1804 - Lewis and Clark Expedition: The "Corps of Discovery", exploring the Louisiana Purchase, suffers its only death when Sergeant Charles Floyd dies, apparently from acute appendicitis.
• 1866 - President Andrew Johnson formally declared the U.S. Civil War over.
• 1882 - Peter Ilyich Tchaikovsky's 1812 Overture debuts in Moscow.
• 1888 - Mutineers imprison Emin Pasha at Dufile.
• 1900 - Japan's primary school law is amended to provide for four years of mandatory schooling.
• 1914 - World War I: German forces occupy Brussels.
• 1920 - The first commercial radio station, 8MK (WWJ), begins operations in Detroit, Michigan.
• 1926 - Japan's public broadcasting company, Nippon Hōsō Kyōkai (NHK) is established.
• 1938 - Lou Gehrig hits his 23rd career grand slam - a record that still stands.
• 1940 - Exiled Russian revolutionary Leon Trotsky is fatally wounded in Mexico City by an assassin's ice axe. He dies the next day.
• 1944 - World War II: The Battle of Romania begins with a major Soviet offensive.
• 1953 - The Soviet Union publicly acknowledged it had tested a hydrogen bomb.
• 1955 - In Morocco, a force of Berbers from the Atlas Mountains region of Algeria raid two rural settlements and kill 77 French nationals.
• 1960 - Senegal breaks from the Mali federation, declaring independence.
• 1968 - 200,000 Warsaw Pact troops and 5,000 tanks invade Czechoslovakia to end the "Prague Spring" of political liberalization.
• 1969 - All four Beatles were together in the recording studio for the final time as they finished the Abbey Road LP.
• 1974 - Congress votes to reduce aid to South Vietnam from $1 Billion to $700 Million. Majority of the cuts were for military supplies.
• 1975 - Viking Program: NASA launches the Viking 1 planetary probe toward Mars.
• 1977 - Voyager Program: The United States launches the Voyager 2 spacecraft.
• 1979 - The East Coast Main Line rail route between England and Scotland is restored when the Penmanshiel Diversion opens.
• 1982 - Lebanese Civil War: A multinational force lands in Beirut to oversee the PLO withdrawal from Lebanon.
• 1986 - In Edmond, Oklahoma, U.S. Postal employee Patrick Sherrill guns down 14 of his co-workers and then commits suicide.
• 1988 - "Black Saturday" of the Yellowstone fire in Yellowstone National Park
• 1988 - Peru becomes a member of the Berne Convention copyright treaty.
• 1988 - Iran-Iraq War: A cease-fire is agreed to after almost eight years of war.
• 1991 - Collapse of the Soviet Union, August Coup: More than 100,000 people rally outside the Soviet Union's parliament building protesting the coup aiming to depose President Mikhail Gorbachev.
• 1991 - Estonia secedes from the Soviet Union.
• 1993 - After rounds of secret negotiations in Norway, the Oslo Peace Accords were signed, followed by a public ceremony in Washington, D.C. the next month.
• 1997 - Souhane massacre in Algeria; over 60 people killed, 15 kidnapped.
• 1998 - The Supreme Court of Canada states Quebec can't legally secede from Canada without the federal government's approval.
• 1998 - U.S. embassy bombings: The United States military launches cruise missile attacks against alleged al-Qaida camps in Afghanistan and a suspected chemical plant in Sudan in retaliation for the August 7 bombings of American embassies in Kenya and Tanzania. The al-Shifa pharmaceutical factory in Khartoum is destroyed in the attack.
• 2002 - A group of Iraqis opposed to the regime of Saddam Hussein take over the Iraqi Embassy in Berlin for five hours before releasing their hostages and giving up.

Births