23rd Infantry Division (AMERICAL) Order of Battle during the Vietnam War

Infantry Battalions

• 2nd Battalion, 1st Infantry Regiment
• 3rd Battalion, 1st Infantry Regiment
• 4th Battalion, 3rd Infantry Regiment
• 1st Battalion, 6th Infantry Regiment
• 1st Battalion, 20th Infantry Regiment
• 3rd Battalion, 21st Infantry Regiment
• 4th Battalion, 21st Infantry Regiment
• 4th Battalion, 31st Infantry Regiment
• 1st Battalion, 46th Infantry Regiment
• 5th Battalion, 46th Infantry Regiment
• 1st Battalion, 52nd Infantry Regiment

Division Artillery

• 6th Battalion, 11th Artillery Regiment (105mm)
• 1st Battalion, 14th Artillery Regiment (105mm)
• 3rd Battalion, 16th Artillery Regiment (155mm)
• 3rd Battalion, 18th Artillery Regiment (175mm /8 inch SP)
• 1st Battalion, 82nd Artillery Regiment (155mm)
• 3rd Battalion, 82nd Artillery Regiment (105mm)
• Battery G, 55th Artillery Regiment (.50cal HMG)

Aviation Units
16th Aviation Group

• 14th Aviation Battalion (Combat)
• 123rd Aviation Battalion (Airmobile)
• 212th Aviation Battalion (Combat)

Division Reconnaissance

• Troop F, 8th Cavalry Regiment (Air)
• Troop E, 1st Cavalry Regiment (Armored)
• Troop F, 17th Cavalry Regiment (Armored)
• Company E, 51st Infantry (Long Range Recon)
• Company G, 75th Infantry (Ranger)
• AMERICAL Scout Infantry Company (Provisional)
• Troop H, 17th Cavalry Regiment

Division Support Units

• 26th Engineer Battalion
• 23rd Medical Battalion
• 23rd Supply & Service Battalion
• 523rd Signal Battalion
• 23rd Administrative Company
• 723rd Maintenance Battalion
• 23rd Military Police Company
• 328th Army Security Agency Company
• 635th Military Intelligence Company
• 3rd Military History Detachment
• AMERICAL Combat Center
• 27th Chemical Detachments
• 87th Chemical Detachments
• 90yh Chemical Detachments
• 10th Public Information Detachment
• 31st Public Information Detachment

Primary Sources:
"Vietnam Order of Battle" by Shelby L. Stanton
http://en.wikipedia.org/wiki/23rd_Infantry_Division_%28United_States%29 (http://en.wikipedia.org/wiki/23rd_Infantry_Division_%28United_States%29)
http://www.americal.org/oob2.shtml (http://www.americal.org/oob2.shtml)

Good Hunting.

MR