Umar, Caliph (Rashidun Caliphate) : All Data

Umar was the second caliph of the Rashidun Caliphate, reigning from 634 to 644. During his tenure, he led the Muslim forces in several significant wars. In 634, Umar oversaw the Battle of Ajnadayn, where the Rashidun Caliphate emerged victorious against the Byzantine Empire. In 636, he played a crucial role in the Battle of Yarmouk, a decisive Muslim victory against the Byzantines, securing the Muslim control over Syria. Umar's rule also witnessed the conquest of Egypt in 639 and the Battle of Nahavand in 642, where the Persian Empire was defeated, leading to the fall of the Sassanian dynasty.