In November 633, Khalid divided his army into three units, and attacked these auxiliaries one by one from three different sides at night, starting with the Battle of Muzieh, then the Battle of Sanni, and finally the Battle of Zumail. These devastating defeats ended Persian control over Iraq. In December 633, Khalid reached the border city of Firaz, where he defeated the combined forces of the Sasanian Persians, Byzantines and Christian Arabs in the Battle of Firaz. This was the last battle in his conquest of Iraq.