August 20

1914:

World War I: German forces occupy Brussels

1940:

Chuchill's speech "Never in the field of human conflict..."

1944:

Allies close Falaise Gap

1968:

The "Prague Spring" abruptly ended when 200,000 Warsaw Pact troops and 5,000 tanks invaded Czechoslovakia

1998:

U.S. Embassy Bombings: The United States military launches cruise missile attacks against alleged Al-Qaeda 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.

636:

Arab forces led by Khalid bin Walid took contol of Syria and Palestine in the Battle of Yarmuk

917:

Tsar Simeon I of Bulgaria invaded Thrace and drove the Byzantines out.