Horace Barlow (Barber) was born around 1828 in Albemarle County, Virginia. Although he was a slave prior to the war, his previous owner or owners are unknown. Barlow lived in Louisiana with his wife Ann, who was born around 1839. The two were married by 1855, while they were both enslaved. Prior to the war, Barlow worked as a brickmaker.

Barlow enlisted as a private in the USCT on April 10, 1863, and mustered into service on April 28 in Carrolton, Louisiana. His service record describes him as 5 feet, 7 inches tall, with black hair, dark eyes, and dark complexion. He served in numerous companies and regiments during the war, due to the circumstances of Louisiana USCT regiments often needing to reorganize into new, consolidated regiments. Barlow first served in Company B of the 95th USCT Infantry Regiment. At some point, Barlow transferred to Company C of the 81st USCT Infantry Regiment. When the 81st USCT combined with another regiment, he became a member of Company B of the new 87th USCT Infantry Regiment. Finally, on August 21, 1865, Barlow transferred to Company B of the 84th USCT Infantry Regiment. He served throughout Louisiana and Texas and was likely present at action in Morganza, Louisiana, and Brazos Island, Texas, where he contracted a fever that he later claimed caused a tumor in his left leg. Barlow mustered out on March 14, 1866, in New Orleans, Louisiana.

Following the war, he and his wife Ann lived Iberville Parish before settling in West Baton Rouge. According to his pension records, he worked as a "day hand on sugar farms and rice farms." Barlow and Ann had three children: George, born December 18, 1861; Letty, born March 15, 1865; and Annie, born August 15, 1876. Horace and Ann finally married legally on July 3, 1877, in Iberville Parish. He originally applied for a pension, claiming the tumor in his left leg caused him to be "totally disabled" by January 1897. However, doctors disagreed about the severity of the tumor and its incapacitating effect on his work. Starting around 1901, Barlow began receiving a pension of $8 a month for "general senility." On July 15, 1904, he died of dropsy, a term for edema. Ann received a pension starting in 1904, which she kept until her death on February 28, 1913.