 Complete the following phrase:  First Russo-Turkish War 15681570 occurred after the conquest of Kazan and Astrakhan by the Russian tsar Ivan the Terrible. The Ottoman sultan Selim II tried to squeeze the Russians out of the lower Volga by sending a military expedition to Astrakhan in 1569. The Turkish expedition ended in disaster for the Ottoman army, which could not take Astrakhan and almost completely perished in the steppes, while the Ottoman fleet was wrecked in the Sea of Azov. The peace treaty between the two sides cemented Russias conquests on the Volga, but allowed the Ottoman Empire to obtain a number of commercial benefits. Ottoman vassal the Crimean Khanate continued its expansion against the Russian Tsardom, but was defeated at the 