The official website for the 1st Infantry Division. The 1st Infantry Division is a combined arms division of the United States Army, and is the oldest continuously serving division in the Regular Army. It has seen continuous service since its organization in 1917 during World War I.

Learn about the leaders and of the 1st Infantry Division. Read about their backgrounds and accomplishments.

The 1st Infantry Division is commonly referred to as "Big Red One." It is the the oldest continuously serving active duty division in the U.S. Army. On June 8, the 1st Infantry Division will celebrate 100 continuous years of service to the nation.

The 1st Infantry Division and Fort Riley executes the Year of Victory during 2024 to recognize the Division’s storied history and legacy of Victory, honor the excellence within the Division and the Fort Riley community, and continue to develop innovative leaders of the future.

Learn about the background and history of the 1st Armored Brigade Combat Team (1ABCT), a unit within the 1st Infantry Division. Read about their leaders and learn about their backgrounds and accomplishments. Find contact information for their battalions.

Learn about the background and history of the 1st Combat Aviation Brigade (1CAB), a unit within the 1st Infantry Division. Read about their leaders and learn about their backgrounds and accomplishments. Find contact information for their battalions.

2023年8月18日 · The Department of the Army announced the 1st Infantry Division Combat Aviation Brigade will deploy to Europe to replace the 3rd Infantry Division Combat Aviation Brigade, as part of a regular rotation of forces to support the United States’ commitment to NATO allies and partners.

Learn about the background and history of the 1st Infantry Sustainment Brigade (1IDSB), a unit within the 1st Infantry Division. Read about their leaders and learn about their backgrounds and accomplishments. Find contact information for their battalions.

The Year of the Warrior 2025 will recognize 1 st Infantry Division’s individual soldiers, their skills, warfighting mastery, enhanced lethality, and continue to develop innovative leaders of the future. More information to follow!

FIRST INFANTRY DIVISION HEADQUARTERS Victory Hall, Building 580 | Reed Ave, Fort Riley, KS 66442 | Ph: 785-239-2222