Thorn was a member of the United States military during World War II and the Korean War. In both conflicts he had Hank "Combat" Kelly and his friend Cookie Novak under his command. Thorn was always weary of the thick-headed Kelly and regularly put him on patrol duty and other menial tasks. Kelly always carried out his ordained missions, but usually in frequently unconventional ways that were viewed by Thorn as Kelly goofing off and frequently lost his temper with private and often put him in the guard house for even the smallest infraction. He commanded Baker Company during both wars.
During World War II, Thorn held the rank of Captain. He saw combat in Anzio, Italy in January of 1944. In March of 1945, he worked with Combat Kelly, Cookie Novak and Allied spy Agent K in dismantling the Wolves, a group of Nazi operatives who sought to reinforce the German defensive. In the spring of 1944 Captain Thorn was in command of the 34th Infantry Division (The Sandstorm Division) seeing combat in Italy in the later half of World War II. Later he was active in Italy with Baker Company. On July 17, 1944, Captain Thorn commanded troops in the South Pacific, liberating Onna Atoll from the Imperial Japanese Army. He was also active on Baker Company operations on Kuma Atoll, and Kuna Atoll in early March of 1945. They returned to Europe later that month where Captain Thorn led Baker Company on the final pushes through Nazi Germany until the death of Hitler.
Captain Thorn later returned to the South Pacific with Baker Company where he saw skirmishes with Imperial Japanese forces on Hagura Atoll, Tsuki Atoll, an unnamed atoll with robot tanks. Lastly after showing bravery on Kabu Atoll, Captain Thorn's promotion to the rank of major thanks to a petition started by Combat Kelly and the members of Baker Company.
During the Korean War, Thorn rose to the rank of major. Thorn was not always stern with Combat and Cookie, often granting them various privileges as situations dictated. For example, when Cookie was captured by the enemy, Thorn -- believing Cookie dead -- awarded him the Silver Star for combat. However, when Combat insisted on going out and finding his friend, a sympathetic Thorn allowed Kelly to go out alone, giving him a bullet proof vest for protection. Later, Major Thorn assigned Combat and Cookie to sentry duty. Combat was depressed after failing to capture the female Chinese soldier known as Yalu River Rosie. Listening to Cookie's pleas to do something about Kelly's depression, Thorn allowed him to go on a five-day leave. Combat then used that time to go out and capture Rosie. Shortly thereafter, Major Thorn was shocked when Cookie Novak made a crash landing on base inside an enemy fighter plane. Thorn then had the plane taken for study and rewarded Cookie by waiting hand and foot over him and providing him with extra rations for the remainder of the evening.
When a high ranking General was captured by Chinese forces, Major Thorn arranged a prisoner exchange and sent Combat Kelly and Cookie Novak to deliver Yalu River Rosie to the Chinese officials. He specifically ordered them not to double-cross the Chinese. However, when the Chinese tried to do that to Combat and Cookie, they fought back freeing the general and recapturing Yalu River Rosie. Thorn was furious that they did not follow orders until the General confirmed what happened. After Combat Kelly and Cookie Novak rescued a Japanese sumo wrestler named Yamakayaka, the sumo requested to become enlisted in the Ground Infantry. Major Thorn refused due to United Nations regulations, however after Yama assisted Combat and Cookie in rescuing the Major from Chinese forces, Thorn pulled some strings that saws Yama enlisted as a G.I.. Taking an active role in combat, Major Thorn led a siege on the Chinese-controlled town of Yongwa, helping to liberate its people from Chinese tyranny. Later, Thorn was captured by Yalu River Rosie and taken to an enemy base. There he was rescued by Combat and Cookie who once more tracked down their old enemy and foiled her plans. Soon after, when Kelly and Novak managed to steal a giant mechanical dragon from the Chinese, Major Thorn led a group of troops to use it as a Trojan horse to attack Chinese soldiers. Later, Major Thorn was captured and placed in a Prisoner of War camp but was soon rescued along with the other prisoners thanks Combat Kelly and Cookie Novak.
Major Thorn spent the remainder of the Korean War commanding over a reformed Baker Company along with Combat Kelly and Cookie Novak. Working on operations to destroy communist supply bridges and train supplies. After defending a small town, after clashing with communist forces in Karyoju, Major Thorn and Baker company were led to a secret communist aircraft factory hidden along the Han River. They later rescued a Korean family, took Hill 333 from communist forces, then led enemy forces out of an ancient temple to prevent its destruction. The Company also clashed with a new prototype enemy tank. In his last recorded appearance during the Korean War was when Major Thorn was captured by enemy soldiers, only to be rescued by Baker Company with the assistance of the Bacardi brothers, former circus performers.
After the Korean War, Major Thorn was put in charge of a Military Police unit in the American Occupied Zone of Germany, and once more was in command of Combat Kelly and Cookie Novak who had become part of the Military Police. When the pair succeeded in capturing a spy from the Russian Occupied Zone, the Major rewarded Combat and Cookie by increasing their ranks to Sergeant.