The366th Infantry Regiment was an all African American (segregated) unit of the United States Army that served with distinction in both World War I and World War II. The unit was unique because it was one of the few Negro (Buffalo Soldiers) units with all its own officers and personnel; the U.S. military did not desegregate until after World War II, and in most of the segregated units, all of the officers were white. During World War II, the unit saw combat in Italy as part of the 92nd Infantry Division (colored), 5th Army.

The 366th Infantry was constituted 16 August 1917 in the National Army as the 366th Infantry and assigned to the 92nd Division and organized at Camp Dodge, Iowa, in November 1917.