For a timeline, visit the YWCA's History page on the YWCA's website.
From Temple University Libraries' YWCA history page:
"The YWCA was founded in New York City in 1858. Initially known as the Ladies Christian Association, the organization was dedicated to improving the "temporal, moral and spiritual welfare" of employed women. In addition to holding religious meetings, the organization opened a boarding house and sponsored recreational activities for wage-earning women. The early Association model proved so successful that women in Boston organized the first official "Young Women's Christian Association" in 1866. YWCA branches quickly sprang up in cities, factories, and college campuses across the country.
The creation of the YWCA was linked to the changing social and economic roles of women in the mid-to-late nineteenth century. Spurred by the manufacturing boom, hundreds of thousands of women poured into industrial cities in search of factory work. But resources for these women, particularly safe housing and inexpensive dining options, were scarce. The goal of the YWCA was to meet the immediate needs of wage-earning women. In addition to hosting recreational clubs, the YWCA also offered classes in professional development, education, and personal improvement.
Though founded as a religious Protestant organization, the YWCA evolved into a global movement that supported gender equality and the rights of working women. In 1894, the World's Young Women's Christian Association was formed, and in 1906 the National Board of the United States YWCA was organized. In 1946, the YWCA publicly acknowledged its commitment to pioneering "an interracial experience" that would be "increasingly democratic and Christian." The YWCA continues to play an important role in local communities and remains dedicated to "eliminating racism, empowering women and promoting peace, justice, freedom and dignity for all."
From Wikipedia:
YWCA USA changed its corporate name from "Young Women's Christian Association of the United States of America, Inc." to "YWCA USA, Inc." in December 2015.