The VFW Chaplain’s Handbook provides us with the history of Chaplains,

"The modern chaplaincy’s roots and origin are essentially in the medieval church. The word chaplain dates from this period. A fourth century story tells of the pagan Roman soldier called Martin of Tours. As Martin and his men were returning from the battlefield in the middle of a severe winter, they met a shivering beggar at the city gate of Amiens. Martin had compassion on the beggar. He cut his cloak in two parts and gave one to the beggar. That night he had a vision of Christ wearing the beggar’s cloak. As a result, Martin converted to Christianity. Martin enraged Emperor Julian by saying, "Hitherto I have served you as a soldier; allow me now to become a soldier to God…” The Emperor later released him from the army. He was baptized and in 371, the people of Tours were so impressed by his holy life and miracles, they made him their Bishop. Martin of Tours later became the patron saint of France and his cloak, considered a holy relic, was carried into battle by Frankish kings. This cloak was called in Latin the "cappa.” Its portable shrine was called the "cappalla” and its caretaker priest, the "cappellanus”. Eventually, all clergy affiliated with the military were called "capellani,” or in French, "chapelains, hence chaplains. The Council of Ratisbon (742) first officially authorized the use of chaplains for armies, but prohibited "the servants of God” from bearing arms or fighting. However, religious figures in this era often went into battle as fighting men with the army. The conflict between the religious function and the military role can be seen in the career of the patron saint of military chaplains, St. John Capistrano, who besides serving as a Church Diplomat led the army at the Battle of Belgrade in 1456. This European tradition extended to colonial America where the chaplain both fought alongside and ministered to his neighbors in the militia. The tradition in colonial America of the fighting chaplain began changing. After the Civil War, chaplains were no longer permitted to carry weapons. And today, chaplains are supposed to be issued a Geneva Convention Identity Card. Chaplains are ordained clergy, endorsed by their faith group to serve all people, regardless of religious or non-religious affiliation.”