one of the successor states to the Mongol empire. Founded in 1443 and centred at Bakhchisaray, the Crimean khanate staged occasional raids on emergent Muscovy but was no longer the threat to Russian independence that its parent state, the Golden Horde, had been even after becoming a Turkish vassal in 1475. Muscovite tributes to the khanates became increasingly perfunctory, and Grand Duke Ivan III formally declared Moscow independent in 1480. His grandson, Ivan IV the Terrible, conquered the other two major Tatar khanates, Kazan and Astrakhan, but turned his attention to the Baltic before attacking the Crimea. Prince Vasily Golitsyn made two failed attempts to subdue this last fragment of the Horde (1687–89), but the khanate of the Crimea survived to stage raids on Russia until Catherine II the Great annexed it in 1783.