One of two brigades of horse artillery attached to the cavalry corps.

Commander: Capt. James M. Robertson (May 28, 1817 – January 21, 1891). Professional soldier, born in New Hampshire; rose from enlisted ranks. He lived in New York after the War.

Strength: 493

Losses: 8; 2 killed, 6 wounded, 0 missing.

Monuments and Memorials of the First Horse Artillery Brigade