Mary Ellen Pleasant was a free black woman entrepreneur in California and a pioneer of black philanthropy. During her ninety years of life, she worked on the Underground Railroad and helped to usher in California’s Gold Rush. She is perhaps most famous for using her enormous financial resources to assist John Brown in his raid on Harpers Ferry. Her continued efforts of racial equality in the West led her to be known as “The Mother of Human Rights in California.” When Pleasant and two African American women were kicked off a street car in San Francisco, she filed suits. Her case, Pleasant v. North Beach & Mission Railroad Company, went to the California Supreme Court. After two years of litigation, the city outlawed segregation in San Francisco’s public transportation. This paper places her efforts squarely in the center of America’s greatest turning points. Time and time again we see how black women, and in particular, Mary Ellen Pleasant, cannot be separated from the endorsement of American entrepreneurship, abolitionism, and human rights.