Just days after the United States entered World War I a small cadre of men established a new agency to direct American Jewry's contribution to the War Department's efforts to provide soldiers' welfare services. The resulting agency, the Jewish Welfare Board, secured a position as the Jewish civilian agency for soldiers' welfare, and thus became American Jews' official representative to the War Department and the only Jewish agency authorized to provide services ranging from religious worship to sports and entertainment, to the nearly 250,000 Jewish men who served in the World War I American military.

Attaining such a position created a singular opportunity for the Jewish Welfare Board. During the war, the government departed from standard policies governing the separation of church and state, and recognized the authority of one Jewish agency over all others. The men behind the Board attempted to use that singular access to state power to shape the identities of Jewish servicemen and to assert the value of Judaism to American society. By virtue of its position under the War Department, the Jewish Welfare Board pushed the country towards a greater acceptance of religious pluralism and simultaneously worked to package Jewishness in terms that made sense within American social and religious norms. Its wartime experiences revealed both the "invisible sectarianism" that governed those norms, and the limits to how much Jews themselves wished to interact with their non-Jewish compatriots.

Through its unique position as American Jewry's official representative, the Jewish Welfare Board shaped a strategy to facilitate Jewish men's full participation in American civic life, while enhancing their commitment to particular forms of Jewish distinctiveness. And it is in the work of the World War I Jewish Welfare Board that conceptions of the United States as a country of three faiths, Protestant, Catholic, and Jew, began to take shape.