The 1st Louisiana Native Guard was originally a Confederate unit, at least in the sense it was part of the state militia of a Confederate state.

The following information is from the official website of the Cabildo...

http://lsm.crt.state.la.us/cabildo/cab10.htm

Statewide by early 1862 more than 3,000 free African Americans had formed military organizations, called Native Guards, and offered their services to the Confederacy. Their duties were similar to those of white home guards--protecting their areas of residence from internal and external threat. They provided their own uniforms, horses, and arms and ammunition. Some were large land- and slaveowners, who, like white planters, opposed the end of slavery and the loss of their possessions. Many free blacks recognized and wanted to maintain distinctions between themselves and slaves or the newly freed. Only a few blacks actually served alongside whites in Confederate units and received Confederate pensions.