 Clayton was raised on his father's farm and received his early education at the Village Green Seminary.In 1862, pursuant to proclamations from President Abraham Lincoln and Governor Andrew Gregg Curtin, he raised a company in Delaware County—this company became Company H of the 124th Regiment, Pennsylvania Volunteers.The 124th Regiment served a nine-month enlistment, commencing in August 1862, and ending in May 1863, during a critical period in the American Civil War.