Abu Ubaidah bin Jarrah was the conqueror of _______?

Abu Ubaidah bin Jarrah was the conqueror of _______?

ابو عبیدہ بن جراح _______ کا فاتح تھا؟
Explanation

The Battle of Yarmouk was a major battle between the army of the Byzantine Empire and the Muslim forces of the Rashidun Caliphate.