World War II Medal of Honor Recipient. He received the award posthumously (presented to his widow) from US Army Brigadier Genera Malcolm F. Lindsey at Fair Mount Park in Philadelphia, Pennsylvania, on May 31, 1945, for his actions as a staff sergeant with Company F, 2nd Battalion, 29th Infantry Division, US Army, on September 13, 1944, at Brest, France. He dropped out of high school in order to support is family, working as a horse groomer for a race track, then as a butcher. In 1939 he established a business delivering groceries in a customized van. In 1943 he joined the US Army, and after his recruit and combat training, he was sent to England in preparation for the D-Day inversion of France. He went ashore with the 1st wave at Omaha Beach on June 6, 1944, but on the following day, his company was accidentally hit by British dive bombers who mistakenly thought they were German soldiers. He was wounded and sent back to England to recover, and about two weeks later, he rejoined his unit. On September 13, 1944, at Brest, France, he single-handedly attacked and captured a German position, prompting the surrender of other German forces in the area. For his heroic action, he was awarded the Medal of Honor. However, he was killed in combat action the following day His Medal of Honor citation reads: "For conspicuous gallantry and intrepidity at risk of his life above and beyond the call of duty. On 13 September 1944, in Brittany, France, the 2d Battalion in its attack on the fortified city of Brest was held up by a strongly defended enemy position which had prevented its advance despite repeated attacks extending over a 3-day period. Finally, Company F advanced to within several hundred yards of the enemy position but was again halted by intense fire. Realizing that the position must be neutralized without delay, S/Sgt. Hallman ordered his squad to cover his movements with fire while he advanced alone to a point from which he could make the assault. Without hesitating, S/Sgt. Hallman leaped over a hedgerow into a sunken road, the central point of the German defenses which was known to contain an enemy machinegun position and at least 30 enemy riflemen. Firing his carbine and hurling grenades, S/Sgt. Hallman, unassisted, killed or wounded 4 of the enemy, then ordered the remainder to surrender. Immediately, 12 of the enemy surrendered and the position was shortly secured by the remainder of his company. Seeing the surrender of this position, about 75 of the enemy in the vicinity surrendered, yielding a defensive organization which the battalion with heavy supporting fires had been unable to take. This single heroic act on the part of S/Sgt. Hallman resulted in the immediate advance of the entire battalion for a distance of 2,000 yards to a position from which Fort Keranroux was captured later the same day. S/Sgt. Hallman's fighting determination and intrepidity in battle exemplify the highest tradition of the U.S. Armed Forces."