Susa Young Gates (1856-1933) is an interesting figure. She is the daughter of famed Mormon and LDS Church president Brigham Young and Lucy Bigelow, his 22nd wife. Perhaps "women's rights advocate" and "Mormon" aren't synonymous, but Gates was indeed a women's rights advocate.
Gates started the Young Woman's Journal in 1889 and it was published until 1929. She also started the Relief Society Magazine in 1915, which was published until 1922. Beyond magazines, Gates wrote nine books (some of which are on Amazon, used); the most well known is probably a biography of her father.
Gates wasn't just about writing though. She was one of the founders of the National Household Economics Organization and was a delegate and officer of the National Council of Women. Gates served as a delegate and speaker to five congresses of the International Council of Women, and in 1901, as a delegate to the International Council of Women in Copenhagen and London, she presented a paper, "Scientific Treatment of Domestic Science," in which she wrote:
Gates attended the University of Deseret (now known as the University of Utah), and Brigham Young academy. She was married at age 16, but divorced (!) five years later. She remarried three years after her divorce. All told, she had 13 children.
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