The Women's Missionary Society of the Pacific Coast was founded on October 29, 1870 by Otis T. Gibson, et al. with the purpose to work among the slave girls in Chinatown, San Francisco, California. The WMSPC mainly taught English and other necessary skills to Asian women and girls who had been rescued from slavery or prostitution in San Francisco's Chinatown. In 1893 the WMSPC joined the Women's Home Missionary Society for this task. Together they opened the "Oriental Home for Chinese Women and Girls" at 912 Washington St. in San Francisco's Chinatown. This building was destroyed by the 1906 earthquake.
Oriental Home and School, as the home was called, was run by the Women's Missionary Society of the Pacific Coast. After formal recognizition by the church, it was incorporated into the Women's Home Missionary Society, later renamed Gum Moon.