The Civil War incorporated all-Black armies on the Union side. It was yet another step closer to giving the black man full rights. After the Civil War, this idea was extended by a Congressional act that created two infantries and four cavalries in 1866. It was still a separate army from the whites, but their role was just as important.
The "Buffalo soldiers" earned their namesake from the Indians of the West. In fact, the Indians had held these soldiers in high esteem. The backs of the soldier's heads also resembled, in the Indian's view, the hair on a buffalo's tuft. The nickname is honorable, in the sense that the Buffalo was a revered animal by the Indians, so to receive such a nickname was a revered honor.
The object of having the soldiers was to protect westward expansion by the United States. They fought battles and the soldiers did some of the behind-the-scenes work behind the wars. They set up telegraphs, mapping expeditions, and helped rebuild forts and towns. They also fought battles against Indians, Mexicans, and other frontier "vagrants." Some members of the Buffalo Soldiers even earned the Congressional Medal of Honor for their great service.
The storied history of the Buffalo Soldiers does not stop with the Indian Wars, though. They were also used in the Spanish-American War, and both World Wars. After WWII, the black soldiers and white soldiers were finally integrated into one army, instead of black and white armies. The Civil War may have been the spark for the Buffalo Soldiers, but the true stepping stone to fame was the Indian Wars of the West.
-Information for this section was gathered using these sites: http://tqjunior.advanced.org/4087/; http://www.imh.org/imh/buf/buftoc.html; http://www.texancultures.utsa.edu/mystery/home.htm; and http://tnt.turner.com/movies/tntoriginals/buffalo/.