The Battle of Yarmuk, fought in 636 AD, was the turning point in Arab history that put a stop to any future Muslim attempt to expand into Europe. Fought between Arab general Khalid ibn al Walid and the Byzantine Emperor Heraclius, it showed that Byzantine arms would not be tarnished by the newfound tactics of the Arabs.After the battle, the Arabs were eager to avoid battle with the Byzantines and instead shifted their efforts eastward into central and southern Asia.The Byzantines,on the other hand, learned from Arab Light Cavalry tactics, and utilized them in their later conquest of Central Europe and Russia.