F Troop is set at Fort Courage, Kansas, a fictional Army outpost in the West, in 1865, the year the Civil War ended. The commanding officer at Fort Courage is the gallant but chronically clumsy and accident-prone Captain Wilton Parmenter (Ken Berry), the descendant of a long line of military leaders. He is awarded the Medal of Honor after accidentally instigating the final charge at Appomattox: he is meant to call "retreat", but he sneezes just as he is about to speak and his troops mistake this for the order "Charge!" His superiors soon realize his ineptitude and post him to remote Fort Courage, a dumping ground for the least useful or trustworthy soldiers.