The 25th Texas Cavalry was part of Col Robert R. Garlands Brigade after it was dismounted at Pine Bluff Arkansas in July 1862. Garlands Brigade consisted of the 6th Texas Infantry, the 24th and 25th Texas Cavalry (dismounted), and Harts (Dallas) Battery of Arkansas Artillery.

While some records may indicate they they were tentively assigned to Walkers Texas Division, I believe that this is a mistake. Garlands Brigade acted in consert with Shaver's/Roane's/Dawson's/Dunnington's Brigade of Arkansas Infantry to construct Fort Hindman at Arkansas Post.

It would seem from the orders from Gen hindman's copybook of telegraph that garlands Brigade was treated almost as an independant command. It certainly recieved orders to move to the Arkansas Post area well before Major Gen. John G. Walker was ever transferred to Arkansas from Lee's Army of Northern Virginia. Garland's Brigade was assigned to be transferred to the east of the Mississippi River for a variety of reasons including even re-enforcement to the Army of Northern Virginia. However events, in November and December of 1862, surrounding the needs of Arkansas Post prevented this transfer.

Almost all of the men, enlisted and officers, were exchanged in April of 1863 at City Point, Virginia. They were to be repatriated back to the Trans-Mississippi Department. But, because of U.S. Grants movements along the Mississippi River around Vicksburg preventing their ability to cross the Mississippi River in May of 1863, it was decided to assign them to The Army of Tennessee.

But, no one wanted them because of the circumstances of the surrender of Arkansas Post. It was Patrick Cleburne who said that he would take them, and them were reorganized into their commands under his supervision in his division.

There was quite a jealous rivalry over getting men from the Trans-Mississippi department to the eastern Theaters and several attempts where made to round up stragglers of these Texas regiments who had been in the hospitals or had otherwise avoided capture at Arkansas Post, who were still west of the Mississippi, to rejoin their original commands in the AoT. Including sending company officers back across the Mississippi to gather up these men. I know this was the case with men in the 24th Texas Cavalry (dis). I see no reason why the 25th would have been handled different.