Marfa Boretskaya

Marfa Boretskaya, known as Marfa the Mayoress (d. after 1478), was one of the wealthiest landowners of late fifteenth-century Novgorod and widow of the posadnik Isaak Boretsky. In the 1470s she led the boyar faction resisting Moscow.

In 1471 she and her sons negotiated Novgorod's submission to Casimir IV of Lithuania and invited Mikhailo Olelkovich to rule, provoking Ivan III's campaign; after the Battle of Shelon, her son Dmitry was executed and Fyodor was exiled in 1475. She continued intriguing with Lithuania until Ivan III annexed Novgorod in 1478, when she was taken to Moscow and her estates were seized.