America entered the “Great War” (1914–18) in 1917 beside the Allies (Great Britain, France, and Russia) against Germany. The war witnessed 10 million fatalities, including 113,000 Americans, and a watershed in race relations.

Meantime, nativism, immigration restriction, anti-sedition laws, and labor shortages spread at home. In the first wave of their Great Migration, 500,000 to 1 million primarily rural southern blacks migrated north for better jobs and opportunities. The migration forecast the “new Negro” and Harlem Renaissance; notable growth of the NAACP, Urban League, and black press; and civil rights protests. Crisis editor W. E. B. Du Bois, commissioned an army captain, urged African Americans to “close ranks” and serve. A. Philip Randolph and Chandler Owen, editors of the socialist and pacifist Messenger, denounced and resisted the draft.

Segregation and racist violence strained the loyalty of blacks, 400,000 of whom served in the military. East St. Louis, Illinois, where factories hired large numbers of black migrants from the South, and Houston, Texas, near Camp Logan, saw riots in the summer of 1917. At least 2 whites and 150 blacks died in East St. Louis. Attacked by Houston civilians and police, black soldiers killed 16 whites; 4 soldiers died. The army hanged 14 of them and sentenced 43 to life in prison. Even so, the NAACP helped launch a Colored Officers’ Training Camp at Fort Dodge in Des Moines, Iowa. It trained 639 officers, less than 1 percent of the army officer corps, while black men and women comprised 13 percent of all service personnel. Ninety percent of blacks mustered as support troops of the American Expeditionary Force and French Army, the latter being more racially tolerant. Black infantry regiments like the 369th and 371st fought bravely on the Western Front. Some 171 members of the 369th were awarded the Croix de Guerre and Legion of Merit, but no black soldier obtained the Congressional Medal of Honor; a member the 371st received it posthumously in 1991.