The National War Labor Board was authorized in March 1918 for the purpose of preventing strikes that would disrupt production in war industries. The first appointments were made the next month. Under the direction of former president William Howard Taft and the labor lawyer Frank Walsh, the board persuaded industry to improve working conditions and wages and open themselves to negotiations with their employees for labor contracts. In exchange for not striking, unions were able to add more than a million members in two years.
After the war, the work of the National War Labor Board was praised by progressives. A statement by Catholic Bishops in February 1919 described the board as follows:
Its main guiding principles have been a family living wage for all male adult laborers; recognition of the right of labor to organize and to deal with employers through its chosen representatives; and no coercion of nonunion laborers by members of the union. The War Labor Board ought to be continued in existence by Congress and endowed with all the powers for effective action that it can possess under the federal Constitution.
Nevertheless, the World War I board was terminated in 1919.
A new board with the same name was created by President Franklin D. Roosevelt in 1942, for essentially the same purpose. By this time, many of the union rights that were encouraged by the World War I board had become rights guaranteed by statute. The new War Labor Board addressed issues of pay inequality based on gender or race. In a ruling in 1943, the board ruled against discrimination based entirely on race:
In this small but significant case the National War Labor Board abolishes the classifications “colored laborer" and “white laborer" and reclassifies both simply as “laborers" with the same rates of pay for all in that classification without discrimination on account of color. The Negro workers in this classification are hereby granted wage increases which place them on a basis of economic parity with the white workers in the same classification.