He offered Sherwood a job at his market after the race season ended, and taught him the butcher trade.
In 1939 Sherwood then began his own business – Sherry's Modern Market – a grocery store on wheels.
Sherry's market offered door-to-door sales of groceries, produce, poultry, meat and dairy products.
One afternoon in 1941 when Hallman stopped by the A. C. Roberts Co. plant in Kimberton to replenish his meat supply, he met Virginia Dieter working in the office.
In September, his division was trying to capture the city of Brest, on the tip of the Brittany Peninsula, south and west of Normandy.
Brest was a key city, and housed a forward German U-Boat base; submarines that were devastating Allied supply ships.
Sherwood's Battalion came under withering fire from several interlocking enemy positions on September 13 and their advance was halted.
Although he normally carried a BAR (Browning Automatic Rifle – a heavy 30 caliber hand held machine gun), Sherwood exchanged it with one of his men for the lighter M1 Carbine, giving him the mobility he needed.
The resulting gap in the German line enabled the GIs to advance another 2,000 yards, to a point from which they launched a successful attack the following day on Fort Keranroux, one of the keys to the defense of Brest.
The Medal of Honor was presented to his wife and 2-year-old son, Sherwood Hallman II, during a ceremony at Fairmount Park Military Police headquarters in Philadelphia on May 31, 1945.
Staff Sergeant Sherwood Hallman was buried with full military honors at the Brittany American Cemetery, St. James France.
The Walter T. Caffrey American Legion Post 602 erected a memorial monument dedicated to Sergeant Hallman at the Spring City Borough Hall on November 18, 1967.
Staff Sergeant Hallman's official Medal of Honor citation reads: For conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty.
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.