Abu Ubaidah was appointed by Khalid ibn al-Walid to siege the Jabiya Gate of Damascus. It was Abu Ubaidah who gave peace to Damascus after Khalid ibn al-Walid attacked the city and conquered it by force. Abu Ubaidah, Sharjeel ibn Hassana and 'Amr ibn al-'As, unaware of Khalid's attack from the Eastern Gate, gave peace to them, which was reluctantly endorsed by Khalid. The Byzantine army was given a cease fire of three days and allowed to go as far as they could with their families and treasure. Others simply agreed to stay at Damascus and pay tribute. The Muslims controlled the road to Emessa, so the Byzantines went west and then north up the Beqaa Valley. After the three-day truce was over, the Muslim cavalry, under Khalid's command, pursued the Byzantine column via the shorter Emessa road and caught them in the northwest Beqaa Valley, just before they entered the mountains en route to Antioch at the Battle of Maraj-al-Debaj.