The Corps d'Afrique at Port Hudson.
The 1st Regiment of the Louisiana Native Guards was sworn into service on September 27, 1862. The 2nd and 3rd Regiments were organized during October and November, respectively.
Actually, the Native Guards were not the first black soliders to volunteer. Major General David Hunter had raised a regiment of black men at Hilton Head, South Carolina, during the spring of 1862, but it was not formally recognized as part of the Union Army. Hunter disbanded the unit on August 9, two weeks prior to Benjamin F. Butler's call for black recruits in New Orleans. Although Secretary of War Edwin Stanton finally authorized Hunter's enlistment of black troops, the 1st South Carolina Volunteers did not complete their reorganization until January 31, 1863. Consequently, the Native Guards were the first black soldiers to be officially mustered into the Union Army during the Civil War.
It should also be noted that Senator Jim Lane began recruiting the 1st Regiment of Kansas Colored Volunteers in August 1862. Although this unit engaged in combat as early as October, it was not mustered into federal service until January 13, 1863, making it the fourth black regiment to enter the United States Army. The famous 54th Massachusetts Infantry did not complete its organization until May 13, 1863, almost eight months after the 1st Regiment of the Native Guards was sworn into service. Finally, a "Black Brigade" was organized in September 1862 in Cincinnati, Ohio, to construct fortifications. However, the three regiments in this brigade were not armed, nor were they given uniforms, and when the threat of a Confederate invasion ended, they were disbanded.