Military conquests were probably the major cause for the early Islamic empire to Expand. According to a Document A written by Muslim historian Ahmad al-Biladuri, in 636 CE the Muslims fought the Eastern Roman empire including the Greeks at Yarmuk. Furthermore, only 24,000 Muslims took part in the battle. Then, with the help of Allah most of the enemies were put to death. Moreover, the Muslims won and took control of Syria. Based on Document c by Fred Donner, some Persian or Aramean nobles were granted stipends or direct salary payments, which cooperated with the Muslims in Iraq. Also, they had to to convert to the Islamic religion, in order to receive their stipends. Document B states, the treaty of Tudmir was signed by the commander of the