it's time to dismount from the horse.

At the end of a hard ride, you should dismount your horse and let it rest.

They were a dismounted Volunteer Cavalry Regiment.

In certain situations during the US Civil War, cavalry units dismounted. This allowed troops to reach a certain position on a battlefield rapidly. The dismounted cavalrymen added quickness and mobility to the infantry units they supported. Historians have noted that perhaps the most decisive use of dismounted was accomplished by Federal cavalry at Nashville on December 15-16, 1864.One factor influencing this tactic was the rough terrain. As riding horsemen, rough terrain hampered the usual operations of cavalry units. On day two of the Nashville battle, There Union dismounted cavalry enveloped the left flank of Confederate infantrymen under General John Bell Hood. The Federals were able to reach the rear of the Rebel force and cut their line of retreat. At Nashville, Hood lost any momentum he had by his march into Tennessee to force General Sherman to curtail his plans of moving to Savannah, Georgia.

His army had horses, but the horse were not bred or trained for battle. His soldiers rode to the battlefield and dismounted to fight.

Confederate General John Bell Hood had a high degree of respect for cavalry forces on both sides of the US Civil War. In his army, especially as the commander of the Army of Tennessee, Hood commented on the tactic of dismounted cavalry. His cavalry units mounted riflemen that were skilled at dismounting and hold in check or delay the advance of the enemy.