Thomas Bestford served with the Union Army during the American Civil War. He volunteered to serve in the 9^th  Regiment, Pennsylvania Cavalry (92^nd Volunteers) on 31^st October 1861, joining up for a term of three years. He was recruited from Dauphin and Luzerne Counties, Pennsylvania.

The 9^th Regiment was mustered at Camp Cameron near Harrisburg, Pennsylvania. It left the state by boat for Louisville, Kentucky, on 20^th November 1861. It then moved to Jeffersonville, Indiana, serving there until 10^th January 1862, when it was ordered to the front in Kentucky until 5^th March 1862. It then saw action in Tennessee.

Thomas Bestford deserted on 13^th December 1862. Desertions were very common during the American Civil War. During the course of the war (12^th April 1861-9^th April 1865) over 200,000 Union soldiers deserted, and slightly more than 130,000 Confederate soldiers did likewise. This represented a rate of 1 in 5 so far as the Union side was concerned, and around 1 in 3 for the Confederacy. Interestingly, only 147 deserters were tried and executed. It seems that both sides were desperate to get men back into service rather than to execute them.