The National Jewish Welfare Board (JWB) was formed on April 9, 1917, three days after the United States declared war on Germany, in order to support Jewish soldiers in the U.S. military during World War I. The impetus for creating the organization stemmed from Secretary of War, Newton Baker and Secretary of Navy, Josephus Daniels. The organization was also charged with recruiting and training rabbis for military service, as well as providing support materials to these newly commissioned chaplains. The JWB also maintained oversight of Jewish chapel facilities at military installations.
In 1921, several organizations merged with the JWB to become a national association of Jewish community centers around the country in order to integrate social activities, education, and active recreation. These merged organizations included the YWHA, YMHA, and the National Council of Young Men's Hebrew and Kindred Association.
In 1941, in a response to a mandate from President Franklin D. Roosevelt, six private organizations - the YMCA, YWCA, the National Jewish Welfare Board, the Traveler's Aid Association and the Salvation Army were challenged to handle the on-leave morale and recreational needs for members of the Armed Forces. The six organizations pooled their resources and the United Service Organizations, which quickly became known as the USO, was incorporated in New York on February 4, 1941.