This comes from the National Archives' Regimental letter, order, guard report, and furlough book.' It begins in June 1863. The 91st's headquarters wagon was captured in November 1862, with all their records. I do not know what happened to the records from then until June 1863.
- some orders before June 1863 that were copied into the company order books.
- regimental orders, June-December 1863
- regimental orders, January-June 1864
- regimental orders, July-December 1864
- regimental orders, January-July 1865