August 20
636 – The army of the Rashidun Caliphate defeats the Byzantine army in the final battle near the Yarmouk river, ending Byzantine rule in Syria. This marks the beginning of moslem conquests outside Arabia.
1191 – During the 3rd Crusade, Richard I of England executes several thousand Saracen hostages at Ayyadieh in retaliation for the perfidy of Saladin
1775 – The Spanish establish the Presidio San Augustin del Tucson, modern day Tucson, Arizona.
1794 – United States troops defeat a confederacy of Shawnee, Mingo, Delaware, Wyandot, Miami, Ottawa, Chippewa, and Potawatomi warriors at the Battle of Fallen Timbers, near the Maumee River in northwestern Ohio, during the Northwest Territory Indian War.
1852 – The steamboat Atlantic sinks on Lake Erie after a collision with the steamboat Ogdensburg, with the loss of at least 150 lives.
1866 – President Andrew Johnson formally declares the end of the American Civil War.
1914 – Brussels is captured during the German invasion of Belgium.
1920 – The first commercial radio station, 8MK (now WWJ), begins operations in Detroit.
1938 – New York Yankees’ player Lou Gehrig hits his 23rd career grand slam, a record that stands for 75 years until broken by Yankees’ Alex Rodriguez in 2013.
1940 – Russian revolutionary Leon Trotsky is fatally wounded with an ice axe by Ramón Mercader, in Mexico City, dying the next day.
1962 – The U.S. government financed NS Savannah, the world’s first nuclear powered civilian ship, embarks on its maiden voyage.
1968 – Warsaw Pact troops invade Czechoslovakia to stop mass freedom protests in Prague.
1975 – NASA launches the Viking 1 probe to become the first craft to launch a landing probe on Mars.
1977 – NASA launches the Voyager 2 spacecraft to encounter the outer planets and go on into interstellar space.
1986 – In Edmond, Oklahoma, U.S. Postal employee Patrick Sherrill murders 14 of his co-workers and then commits suicide.
1991 –More than 100,000 people rally outside the Soviet Union’s parliament building protesting the coup aiming to depose President Mikhail Gorbachev.
1998 – The United States launches cruise missile attacks against al-Qaeda camps in Afghanistan and a suspected chemical weapons plant in Sudan in retaliation for the August 7 bombings of American embassies in Kenya and Tanzania.
2017 – Jerry Lewis dies at his home in Las Vegas, Nevada at age 91.
2020 – Joe Biden accepts the nomination as the 2020 democratic presidential candidate