This Day in History: 0000-08-15

15-20 Aug – Muslim Arab forces under Umar ibn al Khattab routed Byzantine and Ghassanid Arab forces at the Battle of Yarmuk near modern Jordan, permanently capturing Syria and Palestine from Byzantium and setting up the Muslim conquest of Egypt (636).
15 Aug – Julian Carlton, a disgruntled employee of architect Frank Lloyd Wright murdered his mistress, Mamah Borthwick, and seven others, and set fire to the living quarters near Wright’s Taliesin studio (1914).