qnli question: Along with Syria, where did the Muslims extend their control after the Battle of Yarmouk? sentence: However many early history books like the Islamic Conquest of Syria Fatuhusham by al-Imam al-Waqidi state that after the conversion to Islam Muawiyah's father Abu Sufyan ibn Harb and his brothers Yazid ibn Abi Sufyan were appointed as commanders in the Muslim armies by Muhammad.