The Grand Princes of Moscow were rulers of the principality of Moscow from the late 13th century until the early 16th century. They played a crucial role in the unification of the Russian lands and the rise of Moscow as a powerful state. Notable figures include Ivan III, known as Ivan the Great, who expanded the territory and centralized power, and Ivan IV, or Ivan the Terrible, who became the first Tsar of Russia. These princes were often in conflict with neighboring states and the Mongol Empire, which had dominated Russia for centuries. Their leadership helped to diminish Mongol influence and laid the groundwork for the future Russian Empire. The legacy of the Grand Princes is significant in Russian history, marking the transition from fragmented principalities to a unified nation.