Matilda Electa Joslyn Gage (March 24, 1826 – March 18, 1898) was a suffragist, a Native American rights activist, an abolitionist, a freethinker, and a prolific author, who was "born with a hatred of oppression".

Matilda Gage spent her childhood in a house which was used as a station of the Underground Railroad. She faced prison for her actions under the Fugitive Slave Law of 1850 which criminalized assistance to escaped slaves. Even though she was beset by both financial and physical (cardiac) problems throughout her life, her work for women's rights was extensive, practical, and often brilliantly executed.

A daughter of the early abolitionist Hezekiah Joslyn, Gage was the wife of Henry Hill Gage, with whom she had five children: Charles Henry (who died in infancy), Helen Leslie, Thomas Clarkson, Julia Louise, and Maud. Gage lived in Fayetteville, New York for the majority of her life.

Maud, who was ten years younger than Julia, initially horrified her mother when she chose to marry author L. Frank Baum (The Wonderful Wizard of Oz) at a time when he was a struggling actor with only a handful of plays (of which only The Maid of Arran survives) to his writing credit. However, a few minutes after the initial announcement, Gage started laughing, apparently realizing that her emphasis on all individuals making up their own minds was not lost on her headstrong daughter, who gave up a chance at a law career when the opportunity for women was rare. Gage spent six months of every year with Maud and Frank. Gage's son Thomas Clarkson Gage and his wife Sophia had a daughter named Dorothy Louise Gage, who was born in Bloomington, Illinois on June 11, 1898, but died five months later, on November 11, 1898.

The death so upset the child's aunt Maud, who had always longed for a daughter, that she required medical attention. Thomas Clarkson Gage's child was the namesake of her uncle Frank Baum's famed fictional character, Dorothy Gale. In 1996, Dr. Sally Roesch Wagner, a biographer of Matilda Joslyn Gage, located young Dorothy's grave in Bloomington. A memorial was erected in the child's memory at her gravesite on May 21, 1997. This child is often mistaken for her cousin of the same name, Dorothy Louise Gage (1883–1889), Helen Leslie (Gage) Gage's child.

Gage died in the Baum home in Chicago, in 1898. Although Gage was cremated, there is a memorial stone at Fayetteville Cemetery that bears her slogan "There is a word sweeter than Mother, Home or Heaven. That word is Liberty."