In 1871, the General Convention authorized The Woman's Auxiliary to the Board of Missions to coordinate the work formerly conducted by a large number of isolated women's missionary societies. This work included raising funds, publicizing the missionary programs, and recruiting and training women missionaries. The Emery sisters–Mary Abbott, Julia Chester, Susan Lavinia, and Margaret Theresa–were all instrumental in the founding of the organization.
The first General Meeting of the Auxiliary was held in 1874, at which time the women resolved to meet concurrently with General Convention. These meetings came to be known as the Triennial Meetings of the Woman's Auxiliary. In 1889 Julia Chester Emery, who at the time was secretary of the Woman’s Auxiliary, began the United Offering (later renamed United Thank Offering) which provided funds for a wide range of innovative missionary projects.
In 1919, the first National Council Executive Board of the Woman’s Auxiliary was formed to oversee the direction of the work of the women, not only in supporting missionaries, but in social service, religious education, and prayer and worship.
At the 1958 Triennial Meeting, under the direction of the National Council, necessary bylaws were adopted to rename the Executive Board of the Woman’s Auxiliary as the General Division of Women’s Work, which included a designation that diocesan groups would be known as Episcopal Church Women.
Symbolic of the turbulent social climate of the late 1960s, the role of women in the Church went through numerous and significant changes, rendering the Episcopal Church Women unsure of where they fit. Structural reorganizations were initiated aiming to integrate women into the Church on every level. As a part of these changes, Executive Council (formerly National Council) dissolved the General Division of Women's Work in 1968.
Subsequently, the Triennial Meetings were organized by various ad hoc committees until the 1985 gathering, at which time bylaws were adopted forming the Episcopal Church Women (ECW) at the national level. A resolution was filed at the June 1986 meeting of Executive Council confirming that the newly formed Episcopal Church Women “is the same or successor organization to the Woman’s Auxiliary, the General Division of Women’s Work, the Committee for Women, the Triennial Program and Planning Committee, and the Triennial Committee”.
The ECW assumed responsibility for coordinating women's activities in the Church and for organizing the Triennial gatherings.