During the 1920s and 1930s, the United Mine Workers of America was fighting for its existence. The unionized mines of Illinois and Indiana found it difficult to compete with nonunion operations in West Virginia and Kentucky. Wage cuts and declining coal prices left the industry in disarray by the 1930s, with excess production and too many mines and miners. In West Virginia the union had suffered losses in the Mine Wars of the early 20th century, culminating in the hard-fought strikes of the early 1920s.

The pro-labor legislation of Franklin Roosevelt's New Deal brought rebirth. UMWA President John L. Lewis sent hundreds of organizers into the coalfields claiming "the president wants you to join the union." Within a short time, most miners did. Now, with the coalfields highly unionized, Lewis hoped to stabilize the American coal industry by applying consistent union wage rates in all mines. For the first time, he was able to negotiate regional master agreements that would not face the danger of cracking.

The pacesetter of the regional master agreements was the Appalachian Wage Agreement of 1933. Covering West Virginia and the surrounding region, the Appalachian agreement was re-negotiated at approximately two-year intervals until World War II. Lewis slowly brought all the regional agreements closer together, and by 1941 the power of the UMWA had eliminated the traditional wage differentials between the northern and southern coalfields. In obtaining uniform wages and organizing most of the mines, the union halted the practice of cutthroat competition by the reduction of wages. Lewis was moving toward a national labor agreement for the American coal industry, which finally occurred in 1950 as the National Bituminous Coal Wage Agreement.