Ivan IV of Ryazan

Ivan IV of Ryazan continued his father's politics of loyalty towards Moscow.^[1] On June 9, 1483,^[1] he concluded a treaty with his maternal uncle, Grand Prince Ivan III of Moscow, which, as a matter of fact, put the Duchy of Ryazan in the position of a vassal principality.^[2] Dmitry Ilovayski argued that the position of the Grand Prince of Ryazan under this treaty was similar to a viceroy, rather than a ruler.^[2] Ivan IV of Ryazan obliged himself to never betray Grand Prince of Moscow, seek alliances or vassalage to the Grand Duchy of Lithuania, or negotiate with the princes who escaped there.^[2] The relationships with Tatar princes were also to be in accordance with Moscow,^[2] while the Grand Prince of Ryazan, was to pursue and capture the fugitive princes of Meshchera.^[2] By that treaty the Grand Duchy of Ryazan lost many lands.^[2] Ivan IV of Ryazan had to admit the towns of Teshilov, Venyov and Rostovets as domains of Moscow, and never attempt to invade Yelets.^[1]

Upon the order of Ivan III of Moscow, Ivan IV of Ryazan had to send his troops to assist in military campaigns.^[2] In 1492–1494, Ryazanian troops took part in capturing the Principality of Vyazma and a number of Upper Oka towns.^[3] In 1493 Ryazanian troops headed by Prince Fyodor Vasilyevich and his warlord Ivan Inka Izmaylov had to capture Serpeysk and Mezetsk for Moscow, taken by Lithuanians prior to it.^[1] As a result, Ryazanian lands on the west faced multiple attacks from Lithuania. In the peace treaty with the Grand Duke of Lithuania, Alexander, of January–February 1494, Ivan IV of Ryazan declared that he was vassal to Moscow and his lands should not be invaded as if lands of a sovereign prince.^[3]

Ivan IV of Ryazan was married to Princess Agrafena (Agrippina) Vasilyevna Babich-Drutskaya,^[1] daughter of Prince Vasily Ivanovich of Drutsk, on July 13, 1485, in Pereyaslavl of Ryazan. The wedding was conducted by the Bishop of Ryazan Simeon.^[1] His spouse was related to Polish King Casimir IV through her mother.^[3] In the marriage they had a son, Ivan, who succeeded the throne of Ryazan. The latest genealogies claim he had two more sons, Vasily and Fyodor, who are not acknowledged by the respected historians.^[1]

Because of the shortcomings of the agreement of 1496, his brother, Prince Fyodor (d. 1503), bequeathed his appanage to Grand Prince of Moscow, Ivan III.^[1]