This answer comes from part of an earlier answer I gave.
Generally, African-American troops were segregated in separate units away from white troops. Completely African-American units such as the 92nd and 93rd Infantry Divisions, the 758th, 761st, and 784th Tank Battalions, and the 614th and 827th Tank Destroyer Battalions had African-American troops, but both African-American and white officers. Many African-American field artillery units were also formed. The Army also formed many quartermaster, longshore, and other service units composed entirely of African-American troops; they were relegated here because of their lower Army General Classification Test scores. The Army had been warned not to use the test scores as a means of purely classifying intelligence, (it was found that African-Americans generally scored lower on the test because they had been denied educational and life-experience opportunities through segregation and racism; equally-educated white and African-American men scored just the same on the tests) but they did anyway.
Interestingly, black and white combat troops did serve together in the same units in World War II. During the spring of 1945, a severe shortage of riflemen existed in the ETO. Even before the Battle of the Bulge, there was a shortage of 29,000 men. General John C.H. Lee, the commander of the Communications Zone, had planned to scrape up 20,000 personnel from his service units and train them as infantry replacements. General Lee then proposed adding African-American troops as well, and top army commanders agreed. By February 1945, 4,562 Negro troops had volunteered. Of the personnel that volunteered, 38 percent came from engineer units, 29 percent came from quartermaster units, 26 percent came from transportation units, 9 percent came from signal units, 2 percent from ordnance, and the remaining 2 percent from units of other branches. The first 2,800 reported to the Ground Force Reinforcement Command in January and early February, after which the flow of volunteers was stopped.
By the beginning of March, the first men were ready, and were formed into 37 platoons of about 50-60 men each. The platoons were overstrength to provide replacements to themselves. An additional 16 platoons were later made.
The platoons were distributed as follows. A total of ten infantry and armored divisions would eventually receive the volunteer reinforcements:
| Platoons | 6th Army Group | 12th Army Group |
|---|---|---|
| First Group | 12 | 25 |
| Second Group | 4 | 12 |
| Infantry/Armored Division | Platoons Received |
|---|---|
| 1st Infantry Division | 3 |
| 2nd Infantry Division | 3 |
| 8th Infantry Division | 3 |
| 9th Infantry Division | 3 |
| 12th Armored Division | 12 |
| 14th Armored Division | 4 |
| 69th Infantry Division | 3 |
| 78th Infantry Division | 3 |
| 99th Infantry Division | 3 |
| 104th Infantry Division | 3 |
| 106th Infantry Division | 3 |
The first platoons reached 12th Army Group immediately before the Rhine crossing and made an excellent account of themselves in the vicious fighting. In the vast majority of units, keeping the white and black troops from mingling was simply an afterthought. When the African-American platoon in Company B, 16th Infantry Regiment fell to squad strength due to losses, it was organized as a squad within a white platoon.
Known companies that received or utilized African-American fourth platoons at any point included:
| Infantry Division | Companies |
|---|---|
| 1st Infantry Division | B/16, B/18 |
| 2nd Infantry Division | C/9 |
| 9th Infantry Division | G/39, E/60 |
| 69th Infantry Division | K/271, F and K/272, G/273 |
| 99th Infantry Division | E/393, K/394 |
| 104th Infantry Division | G/413 |
The assignments were not fixed, and the platoons were often moved between companies and battalions as needed.
Morale: Excellent. Manner of performance: Superior. Men are very eager to close with the enemy and to destroy him. Strict attention to duty, aggressiveness, common sense and judgment under fire has won the admiration of all the men in the company. The colored platoon after initial success continued to do excellent work. Observation discloses that these people observe all the rules of the book. When given a mission they accept it with enthusiasm, and even when losses to their platoon were inflicted the colored boys accepted these losses as part of war, and continued on their mission. The Company Commander, officers, and men of Company "F" all agree that the colored platoon has a calibre of men equal to any veteran platoon. Several decorations for bravery are in the process of being awarded to the members of colored platoons.
The Negro platoons of the 99th Division, characterized as employed "just as any other platoon,"
. . . performed in an excellent manner at all times while in combat. These men were courageous fighters and never once did they fail to accomplish their assigned mission. They were particularly good in town fighting and [were often used as the assault platoon with good results. The platoon assigned to the 393rd Infantry is credited with killing approximately 100 Germans and capturing 900. During this action only three of their own men were killed and fifteen wounded."
The 104th Division, whose platoons had joined while the division was defending the west banks of the Rhine at Cologne, commented: "Their combat record has been outstanding. They have without exception proven themselves to be good soldiers. Some are being recommended for the Bronze Star Medal."
General Edwin P. Parker of the 78th Infantry Division expressed a wish to obtain more Negro troops.
The infantry platoons in 12th Army Group were assigned three per division, with one platoon going to each infantry regiment. They were then sent as a fourth rifle platoon to an infantry company. Divisions that received platoons included the veteran 1st, 2nd, 8th and 9th Infantry Divisions, and the 69th, 78th, 99th, 104th, and 106th Infantry Divisions.
In Sixth Army Group, the first twelve platoons went to the 12th Armored Division, who organized them into three companies, one per armored infantry regiment. The four platoons of the second group went to the 14th Armored Division, who also made them into a company, and they served in Combat Command R.
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