Shelby's Iron Brigade Brigade. The 3rd Brigade Combat Team, 1st Infantry Division was known as the Iron Brigade from its formation in 1917 through World War I, World War II and Vietnam, until some time in the early 2000s when, for reasons that are still unclear, the name was changed to Duke Brigade. The unit crest was an Iron Cross in a triangle, it appears that that was also changed. The 3rd Brigade of the 4th Infantry Division is also known as the Iron Brigade. Its unit crest is similar to the medals issued to veterans of the both Western and the Eastern
Battle of the Iron Triangle were clearing the road past the An Dien bridge. Working at night with flash lights to avoid PAVN observation and fire, they removed 38 antitank mines from the route of advance. Weakened by casualties, the 52nd Infantry made very little progress on 2 and 3 June, and the 43rd Regiment was still being blocked by the PAVN 272nd Regiment. Đảo then ordered his 48th Infantry across the Thi Thinh south of Bến Cát, to pass through the 52nd and take An Dien. While the PAVN artillery continued to pound ARVN positions, two battalions of the 48th crossed into the Iron