Thanks for the information from the pension applications. Notice that MRB states that he was in prison at Camp Douglas. This is true for the period after being transferred from Camp Randall in 1862. Since MRB surrendered with the rest of his command at Island Ten in early April 1862 and exchanged at Vicksburg in September of that year, he could truthfully claim to have been in prison for about six months.
MRB states, "I was in prison in Camp Douglas, Chicago." That's correct for his earlier service.
He correctly remembers field officers of the 1st Alabama-Tennessee-Mississippi as Col. Alpheus Baker and Lieut. Col. William L. Avery. His first captain was Joshua Morse, which sounds like Moss. He also mentions a captain named Harris, which could be E. Pickens Harris, 2nd Lieut. of Co. "B", 37th Mississippi Regt. Harris kept the company roll up to February of 1863, when he became a commissioned officer. If MRB actually served with this company in the 37th Mississippi, it's a little odd for him not to name other officers, as he did with his first regiment.
Notice that MRB states that he "was not in active service at surrender; was in prison at Nashville, Tenn for a while, but was taken over the Ohio river by the Union Army into Indiana & held." This would be quite like his experience as a Confederate deserter. These men were kept in camp apart from other captured Confederates until they could be given the oath. Afterwards these men were taken north of the Ohio River and released. Part of the conditions of release required that they remain north of the Ohio River until the war ended.
If MRB was a prisoner of war in 1864-65, we would have a record of it in his military service file.
Records of the 54th Alabama Regiment are in poor condition - many missing or destroyed rolls. Records of the 37th Mississippi are in good condition, complete into the spring of 1864. Anyone who ever belonged to the regiment through that period should have a service file.
The pension application includes strong statements which would lead most people to accept MRB's claim of service in the 37th Mississippi. They include mention of a company officer from that company. I will check the names of witnesses later. The missing service file in that regiment and the oath of allegiance with records of the 54th Alabama Regt. lead me to believe otherwise.