During the Sicily campaign, Chilson received the Combat Infantryman Badge (later awarded the Bronze Star Medal based on award of the CIB) for combat actions on July 11 to 31, 1943. In February 1944, the 45th Division reinforced the beachhead at Anzio. He received a Purple Heart for being wounded by shrapnel near Carroceto, Italy on February 15, 1944. On February 16, near Aprilia, Italy, he and three other American soldiers were captured by German soldiers after running out of ammunition in a firefight and were made litter-bearers for the German forces. The four American soldiers managed to escape on February 17, taking four enemy prisoners with them. This then led to the capture of 40 enemy soldiers by Chilson. He was awarded a Silver Star.