During Operation J.E.B. Stuart in the Spring of 1968 in I Corps,
North of the Cau Viet River and 3 miles south of the
North Vietnam border,
the 3rd Squadron of the 5th Cavalry Regiment, along with a portion of
D Troop 3/5th's Aero Scout Platoon,
was under the operational control of the 1st Cavalry Division.

The 1st and 2nd Battalions of the 5th Cavalry Regiment (part of the 1st Cav Division) and the 3rd Squadron (Black Knights) conducted an armed reconnaissance sweep to the north under the same commander.

That was the first time since the Korean War that the entire
5th Cavalry Regiment
was on line together in a combat operation.