Wife No. 19 is the story of one of Brigham Young's 55 wives, and her experiences with polygamy and the Mormon Church. Ann Eliza Young wrote her autobiography in order to inform the rest of the United States, so disengaged with the goings-on in Utah, the bondage Mormonism and polygamy held on women. She didn't publish the book until 1876, after Brigham Young's death, because he so opposed her work and testimony against his church, and because their divorce had been so public and volatile.

Ann Eliza Young, born in 1844, was the 19th wife of Brigham Young, well-known leader of the early Mormon Church and husband to 55 women. After rebelling from Mormon teachings, rejecting the idea that God intends men to have plural marriages, and divorcing her husband, Ann Eliza toured the country, speaking, writing, and campaigning to end polygamy in the United States. Her eventual testimony before Congress in 1875 helped secure the Poland Act, which enabled the Federal government to end polygamy in Utah. Ann Eliza was married three times and had two children, both from her first marriage. She continued to fight for women's rights until her death.