It was named in honor of Buffalo Bills and the University of Oklahoma All-American football player Bob Kalsu who was killed serving in the Vietnam War.

[2] After Operation Iraqi Freedom 1 (OIF1), FOB Kalsu was occupied by Company A, 1st Battalion, 152nd Infantry Regiment, Indiana Army National Guard from October 2003 to January 2004 acting as a quick reaction force (QRF) for Main Supply Route (MSR) Tampa and conducting combat patrols.

The base was then occupied by B Co, 2-505th Infantry Regiment, 82nd Airborne Division from January 2004 to May 2004 effectively conducting combat patrols and acting as the QRF for MSR Tampa.

Second Lieutenant Emily Perez was stationed at FOB Kalsu in September 2006 when, while leading a convoy conducting re-supply operations in the vicinity of Al-Najaf, her HMMWV hit an IED, making her the first female West Point graduate to be killed in Iraq.

[7] From October 2006 to December 2007, FOB Kalsu was occupied by the 4th Brigade Combat Team (Airborne), 25th Infantry Division headquartered at Fort Richardson in Anchorage, Alaska.