On the 24th of March, 1837, Abraham was born in the small town of Bedford in south central Pennsylvania. He attended the US Military Academy at West Point and graduated 21st in a class of 22 cadets in the Class of 1859. Two fun facts about this class are that all cadets would go on to serve in the Civil War and five would serve in the Confederacy. Abraham became a Second Lieutenant in the 2nd Cavalry Regiment before serving with the 5th Cavalry Regiment as a First Lieutenant in April of 1861. He displayed gallant and meritorious service at both the Battles of Todds Tavern and Gaines' Mill and was promoted after each of those battles. It was his actions on the 10th of May, 1864, however, during a battle at Davenport Bridge that would earn him the Medal of Honor. The citation reads:

By a gallant charge against a superior force of the enemy, extricated his command from a perilous position in which it had been ordered.

Before moving on, I want to point out that I had a very hard time finding information on, what was being referred to as the Battle of Davenport Bridge. This was mentioned a few times yet I was unable to find a Civil War battle of that name. The official information says that Abraham was at Davenport Bridge, Virginia on the 10th of May, 1864, which is eighteen miles from Spotsylvania Courthouse and sixty miles from Chester, both which had major battles happening on the 10th of May. At this time, I am unsure if he was a part of the Battle of Chester Station or the Battle of Spotsylvania Courthouse, even though it is more likely that due to location, the latter was more probable.

With that discrepancy out of the way, we will continue on with Abraham, now a Major in June of 1869 with the 6th US Cavalry. With the Civil War over, he participated in the Apache Wars and the Battle of Cibecue Creek on the 30th of August, 1881. Five years later Abraham was a Lieutenant Colonel and eventually became the commander of the Cavalry and Light Artillery School in Carlisle, Pennsylvania, as a Colonel in 1891. When the Spanish-American War began, he accepted a field commission as Brigadier General with the 2nd US Division of the 7th Army Corps. He was in Cuba from the 16th of January, 1898 until the 1st of April, 1899. Two years later, Abraham retire from the Army on the 25th of March, 1901 after almost forty-two years of service. Eight months later, Abraham died at the age of sixty-four. He and his wife Sarah had three sons, Samuel, Walter, and Percy. All three served in the US Army: Samuel ended as a Colonel after 31 years, Percy was also a West Point graduate and died in France as a Colonel due to a railroad accident, and Walter was a Corporal when he died in 1895 at the age of 25. Their father, Abraham Kerns Arnold, and their mother are buried in the Saint Philip's Church Cemetery in Garrison, New York.