There are some oddities in this man's record. His cards are filed under the 8th Mississippi Cavalry. There are only two cards in his file that show him as a part of that unit, but they show him as a member of Company G, which was previously known as Duke's Company or Duke's Company of Independent Scouts (raised in Itawamba County). This company appears to be one of the four companies that were combined with the six companies of the 19th Mississippi Cavalry Battalion to form the 8th Cav. Regiment. The two cards are from the only two muster rolls extant of Company G. One covers the period Nov. 2, 1863, to May 11, 1864. It states that Davis is absent, and the reason given is that he is a paroled prisoner having been captured at Port Hudson, 9 Jul. '63, It states that he was enlisted by Capt. Duke at Buena Vista on Jany 1, but does not give the year. The other card overlaps the first one by date, covering the period from Mar. 1 to Oct. 31, 1864. It repeats the enlistment information except to say that the date he enlisted was Jul. 1, 1864. It shows him absent - paroled prisoner captured at Vicksburg. The only records in his CMSR that list him as a member of Co. B, 8th Mississippi, are Union POW records. However, they show him to be a member of Company B, 8th Mississipi Infantry and not Cavalry. Those records indicate that he was captured at Graysville, GA. on Nov. 27, 1863, which would have been in conjunction with the Battle of Ringgold Gap. That would match up with the presence at that battle of the 8th Infantry, but certainly not of the 8th Cavalry. He was eventually taken to Rock Island, Illinois, where he signed (with his mark) an oath of allegiance on June 19, 1865. And here is another oddity - he actually signs two oaths. Both of them show him to have a dark complexion, dark hair, and gray eyes; to be 5'7" tall and 30 years of age, and a resident of Burleson (or Burleston), Franklin County, Alabama. One states that he is a member of Company B, (no regiment given) Mississippi Infantry. The other says he is a part of Company D, 8th Mississippi Cavalry.
Here is my two-cents worth: He joined Capt. Duke's Company in January 1863 (the July 1864 date being a clerical error), and that unit operated independently, and was a part of the defenses around Port Hudson/Vicksburg. (This is an assumption as I could not find a record confirming that). He was captured at one of those two places, was paroled, and rather than rejoining the 8th Cavalry, enlisted in the 8th Infantry and was subsequently captured at Graysville and imprisoned at Rock Island for the duration of the war.