"Down the Volga:" There were numerous Russo-Kazan wars, usually involving Moscow and Crimea backing various claimants for the Kazan throne, but Kazan (700e, 25s) was too far away to be dealt with easily. Advanced forts were built at Vasilsursk on the Volga below Nizhny Novgorod (1523: 533e) and Sviyazhsk (1551: 675e, 25s) near Kazan. Kazan was conquered in 1552. In 1554 Moscow installed a Nogai prince on the throne of Astrakhan. When he rebelled, Russia annexed Astrakhan (1556: 700e, 1000s). (This enormous expansion to the southeast presumably depended on river transport down the Volga, but this is not clear from the English sources.) In the First Russo-Turkish War (1568–1570), the Ottomans tried and failed to retake Astrakhan for Islam. Following the Livonian War, intermediate forts were built on the Volga: Samara (1586: 300s, 800e), Saratov (1590: 450s, 500e), Tsaritsyn (Volgograd) (1589: 800s, 400e). Between the Volga and Urals Ufa (350s, 1100e) was founded in 1574.