Harriet Taylor Mill (1807 – 1858) was a philosopher and women's rights advocate. She married John Stuart Mill in 1851 after a 21-year friendship and love affair (during most of which she was married to John Taylor). Although she and Mill shared an enthusiasm for women's liberation, they differed in details; she believed that women should be educated and encouraged to enter public life and to pursue careers, while he believed that the removal of legal and educational barriers to women's independence would accomplish equality between the sexes, by granting women independence within marriages.
Mill called her a valuable contributor to much of his work. She also authored her own works, including Enfranchisement of Women.
Harriet Taylor Mill died in Avignon after developing severe lung congestion, on 3 November 1858.