Ivan III or Ivan Fyodorovich (Russian: Ива́н Фёдорович) was the Grand Prince of Ryazan (1427–1456) and younger son of Grand Prince Fyodor II of Ryazan. During his reign, he retained good diplomatic relationships with both the Grand Duchies of Lithuania and Moscow. He signed treaties with both Vytautas of Lithuania and Vasily II of Moscow, and sent his children to the court in Moscow for safety. Towards the end of his life, he took monastic vows and was succeeded by his eight-year-old son, Vasily.