The 54th Massachusetts Infantry Regiment was an infantry regiment that saw extensive service in the Union Army during the American Civil War. The unit was the second African-American regiment, following the 1st Kansas Colored Volunteer Infantry Regiment, organized in the Northern states during the Civil War. Authorized by the Emancipation Proclamation, the regiment consisted of African-American enlisted men commanded by white officers. The 54th Massachusetts was a major force in the pioneering of African American civil war regiments, with 150 all black regiments being raised after the raising of the 54th Massachusetts.

During the American Civil War, the United States Army, the land force that fought to preserve the collective Union of the states, was often referred to as the Union Army, the Grand Army of the Republic, the Federal Army, or the Northern Army. It proved essential to the restoration and preservation of the United States as a working, viable republic.