Miles Carey (Cary) was born in 1834 in Albemarle County, Virginia. Carey was a slave working as a farmer and laborer for a Mrs. Woods in Suffolk, Virginia. Mrs. Woods eventually married Owen R. Flynn, the owner of Carey's eventual wife Maria. Around 1857, Miles and Maria Carey were married. They had two sons: Johnny, born around 1867; and Daniel, born around 1869. At some point before the war, Miles, Maria, and their owners moved from Suffolk to Portsmouth, Virginia.

Carey enlisted at the age of 29 as a private on January 1, 1864, and mustered in on January 11 at Fort Monroe, Virginia. His service record described him as 5 feet, 9 inches tall, with dark hair, dark eyes, and light complexion. He served in Company D of the 2nd USCT Cavalry Regiment. Carey served on duty throughout Virginia during the war. On March 9, 1864, he engaged in action in Suffolk, where he lost equipment. In June of 1864, he suffered a kick from a horse near Richmond and Drewry's Bluff that later caused rheumatism. From August 17 to February 8, 1865, Cary was absent while in the hospital. Later, he also served on detached duty in the ambulance corps. While in Texas, he may have also started to develop partial blindness due to the light and heat of the beaches on the Gulf of Mexico. He mustered out on February 12, 1866, from Brazos Santiago.

Following the war, Carey worked as a laborer. He lived in Portsmouth with his wife Maria and their two sons, Johnny and Daniel. He first applied for a pension in 1890, but a doctor rejected it, not believing his leg and eyesight issues completely prevented him from working. With more witnesses testifying on his behalf, he was able to start receiving a $6-per-month pension in 1893. His pension was increased to $12 a month in 1894 due to his increasingly bad eyesight. Carey spent the last 5 months of his life bedridden due to illness. He died on May 30, 1896, in Portsmouth at his home due to complications of asthma, dropsy and other diseases. His wife Maria moved across the street after his death to continue raising her children. She started receiving a widow's pension of $20 a month in 1916.