Matilda Joslyn Gage (24 March 1826 – 18 March 1898) was a prominent nineteenth-century American feminist and suffragette, a writer, newspaper editor, and associate of Elizabeth Cady Stanton. Her youngest daughter Maud married L. Frank Baum.
Matilda Joslyn Gage was the daughter of Hezekiah Joslyn, an early abolitionist; she married businessman Henry Hill Gage. The oldest of their five children, Charles Henry Gage, died in infancy. The other four survived into adulthood:
Helen married a man with the same last name, Charles Gage; their daughter Leslie Gage was one of Frank and Maud Baum's favored nieces. Thomas Clarkson's daughters included Dorothy Gage and Matilda Jewell Gage.
(The two older Gage siblings were successful at business and prominent in civic affairs. When Baum's Bazaar, the author's Aberdeen, South Dakota store, failed in 1890, Helen Leslie Gage bought the concern from the bank in the foreclosure sale and re-opened it as the H. L. Gage Bazaar.)
Matilda Joslyn Gage encouraged her son-in-law Frank Baum to publish the stories he made up and told to children. In her advanced years, she spent six months of each year living with the Baums.