The northern part of the Eastern Province was first inhabited by the Lakhmids around 300 AD, with the coastal regions claimed by the Sasanians but governed by the Lakhmids. Much of the Eastern Province was under Sasanian rule at the time of Muhammad. The entire Arabian Peninsula fell into Muslim hands during the Rashidun Caliphate and the Muslim conquest of Persia, after Muhammad's death. The region stayed stable during the first three Islamic caliphates.