Her works often stressed the historic accomplishments of women and the way in which men had frequently taken credit for or denied women's contributions. Gage herself was denied recognition of her achievements when she left the mainstream women's suffrage organization to form a more radical group; the resulting animosity led Anthony and Stanton to remove references to Gage in their book on the history of the suffrage movement. Because of this lack of documentation on Gage's role, she has often been overlooked by the generations that followed her.

She and her husband were active in the antislavery movement, and their home in New York State was reportedly part of the Underground Railroad, which helped escaped slaves find freedom.