[1] Hagemeister was drafted into the United States Army from his birth city of Lincoln, Nebraska, in May 1966, during a break from his university studies.

During a firefight on that day, in Binh Dinh Province, Republic of Vietnam, Hagemeister repeatedly exposed himself to enemy fire in order to aid wounded comrades.

[5] Specialist Hagemeister's Medal of Honor citation reads: For conspicuous gallantry and intrepidity in action at the risk of his life above and beyond the call of duty.

Hagemeister's platoon suddenly came under heavy attack from 3 sides by an enemy force occupying well concealed, fortified positions and supported by machine guns and mortars.

Hagemeister unhesitatingly and with total disregard for his safety, raced through the deadly hail of enemy fire to provide them medical aid.

Hagemeister continued to brave the withering enemy fire and crawled forward to render lifesaving treatment and to offer words of encouragement.

Unable to remove the wounded to a less exposed location and aware of the enemy's efforts to isolate his unit, he dashed through the fusillade of fire to secure help from a nearby platoon.