when muhammad bin saud died in 1765, his son abdulaziz bin muhammad al saud who was a dedicated student of muhammad ibn abd al wahhab, became the leader of the emirate of diriyah. in his reign, the emirate of diriyah expanded in territory throughout the arabian peninsula. in the eastern part of the peninsula, abdulaziz bin muhammad al saud got al-hasa, qatar, al-buraimi and bahrain under his influence. in the western part of the peninsula, abdulaziz bin muhammad al saud conquered parts of the hejaz region. during the conquests of abdulaziz bin muhammad al saud, the saudi state got involved in a war with the ottomans. at this stage, the campaigns of the ottomans against the saudi state failed, and abdulaziz bin muhammad al saud was expanding his territory inside ottoman territories. with the death of abdulaziz bin muhammad al saud in 1803, his son saud bin abdulaziz al saud became ruler. saud bin abdulaziz al saud conquered the holy cities of mecca and medina for a few years, which gave him the title of custodian of the two holy mosques. eventually the egyptians, who were supported and led by the ottomans, destroyed the powers of al saud in 1818. it marked the end of the first saudi state.