Upon the death of Peter the Great in 1725, Catherine, Peter's wife succeeded to the throne of the Russian Empire as Czarina Catherine I. Together with Austria, Russia, under Empress Anne, Catherine I's niece, engaged in a war against the Ottoman Empire from 1735 until 1739. The Treaty of Belgrade signed on 18 September 1739, ended this war and resulted in Ottoman recovery of Belgrade and other territories from Austria, but the loss of the port of Azov to the Russians. However following the Treaty of Belgrade, the Ottoman Empire was able to enjoy a generation of peace as Austria and Russia were forced to deal with the rise of the Prussians under King Frederick the Great.