RALEIGH, N.C. (AP) — The Civil War commemorations planned for the next several years have revived an unsettling debate that lingers 150 years after the conflict: how to view the role of African Americans in the Confederacy.

Confederate law prohibited slaves from serving as soldiers until March 1865, when it was changed in a last-gasp effort to strengthen troop numbers.

Most Civil War historians agree black slaves and even some free blacks contributed crucial manpower to the Southern war effort — but it was mostly menial work done under duress or for survival, not out of support for secession.

Yet efforts to depict blacks as Confederates persist.

The Museum of the Confederacy in Richmond, Va., once sold black toy soldiers, clad in Confederate gray. They were pulled from shelves in 2010 after complaints.