The 2nd National flag of the Confederacy, the "Stainless Banner," was adopted in 1863 resulting from battlefield confusion between the Confederate 1st National Flag (The "Stars and Bars") and the Federal flag. It was used until March 1865, when a red vertical stripe was added to prevent it being mistaken for a flag of truce or surrender.

The Texas state flag was flown to designate that the 37th was part of the organizational structure of the state of Texas. The flag was adopted in 1839, was flown by the Republic of Texas and is still flown as the Texas state flag.

The Van Dorn battle flag was the most common battle flag of the Confederate Army of the Trans-Mississippi and was flown by troops from Texas, Arkansas, Louisiana and Mississippi. It is highly unlikely that the 37th ever flew or fought under the Battle Flag of the Army of Northern Virginia.

Terrell's personal banner flew with him starting with his first command in 1863, the 1st Arizona Cavalry, and accompanied him into Mexico after the War during his brief service under Napoleon III.