4:21st Infantry

• Origins: The 4th Battalion, 21st Infantry Regiment ("Gimlets") traces its lineage back to the original 21st Infantry, which was organized in 1861 during the Civil War as part of the Army of the Ohio. • Hawaiian Roots: The 21st Infantry Regiment became known as the "Gimlet" regiment while stationed in Hawaii in the early 20th century, a nod to their tough and unyielding character. • World War II Service: The 21st Infantry served valiantly in the Pacific Theater, participating in campaigns in New Guinea, Leyte, and Luzon, earning multiple Presidential Unit Citations. • Korean War Bravery: The regiment fought in the Battle of Osan, the first significant American engagement of the Korean War, helping delay North Korean advances. • Vietnam Service: 4/21 Infantry was activated for Vietnam in 1967 as part of the 11th Infantry Brigade, Americal Division, and was heavily engaged in operations throughout Quang Ngai province. • My Lai Incident: The 4th Battalion, 21st Infantry operated in areas adjacent to the infamous My Lai Massacre, and some of its soldiers later played roles in reporting abuses. • Expertise in Jungle Warfare: During the Vietnam War, the battalion became adept at jungle warfare, frequently conducting long-range patrols and ambushes. • Post-Vietnam Deployments: After Vietnam, 4/21 Infantry was stationed at Fort Ord, California, and later at Schofield Barracks, Hawaii, participating in multiple training exercises and rapid deployment missions. • Modern Era Assignments: In the 21st century, 4/21 Infantry has deployed to Iraq in support of Operation Iraqi Freedom, conducting counterinsurgency operations and training Iraqi Security Forces. • Distinctive Insignia: The battalion’s insignia features a gimlet tool, symbolizing the regiment's nickname and their ability to "bore through" enemy defenses.