Events By Place Byzantine Empire August 20 — Battle of Yarmuk: Khalid ibn al-Walid's victory against the Byzantine army results in the Byzantine Empire losing Roman Syria to the Muslim Arabs. Persian Empire Battle of al-Qādisiyyah: The Sassanid Persian Empire is conquered by the Muslim Arabs. Europe Rothari marries Queen Gundeparga, and becomes king of the Lombards. Asia The city of Basra, Iraq is founded on a canal by Caliph Omar. The Xumi Pagoda of Zhengding, China, is… (More on 636)