The title "Grand Duke of Moscow" was used by the rulers of the principality of Moscow from the late 13th century until the early 16th century. This title signified a high rank within the Russian nobility and was often associated with the expansion of Moscow as a powerful political and cultural center. The Grand Dukes played a crucial role in unifying the various Russian principalities. The most notable Grand Duke was Ivan III, also known as Ivan the Great, who reigned from 1462 to 1505. He significantly expanded the territory of Moscow and laid the foundations for the future Tsardom of Russia. The title eventually evolved into that of the Tsar, marking the transition from a principality to a centralized state.