The Lutheran Church--Missouri Synod, at the 1938 national convention, resolved that the work of women in the church should be officially recognized and that a women's organization should be formed. As a result, a local committee in the Oregon-Washington District (now the Northwest District) was formed. Women from many congregations sent delegates to an organizational convention at Trinity Lutheran Church, Portland, Oregon, on April 29, 1942. Until a Synod-wide name could be chosen, the Oregon-Washington organization was known as the Federation of Lutheran Women of the Oregon, Washington and Idaho District. The convention of the national organization in Chicago in July, 1942, adopted the name "Lutheran Women's Missionary League." The term "International" was added a few years later in 1951. The first District convention was held at Zion Lutheran Church, Portland, in 1944.

The original objectives have not changed substantially over the years: (a) to develop and to maintain a greater mission consciousness among the women of Synod; and (b) to gather funds for mission projects, sponsored by Synod, especially such for which no adequate provision has been made in the budget.

The Oregon-Washington-Idaho District was the name from 1941-1947. As the organization grew, it was divided into smaller units and renamed as follows: In 1948 Idaho was released to join with northern Utah to form the Idaho-Utah District. The resulting Oregon-Washington District existed from 1948 to 1952. From 1952-1956 it was known as the Northwest District. The 1956 Northwest District LWML convention resolved to divide into two groups: the Oregon District and the Washington District. In 1964 the Alaska societies were assigned to the Puget Sound Zone of the Washington District; that District then became known as the Washington-Alaska District.

In 1953 the international convention of the LWML was held in Portland, Oregon.

Each district is divided into zones. The districts hold biennial conventions and publish a newsletter. The zones sponsor regular rallies and other events designed to achieve the objectives of the organization.