Alexis of Moscow was the Tsar of Russia from 1645 until his death in 1676. He was the second ruler of the Romanov dynasty, which began with his father, Michael I. Alexis is known for his efforts to modernize Russia and strengthen its central authority, as well as for his role in the Time of Troubles that preceded his reign. During his rule, Alexis implemented various reforms, including changes in the military and administration. He also faced challenges such as the Cossack rebellions and conflicts with neighboring countries. His reign marked a significant period in Russian history, laying the groundwork for future developments.