Montgomery attended Chilocco Indian Agricultural School in Northern Oklahoma before transferring to Carnegie Highschool.

For his service during World War II, Jack Montgomery was awarded the Medal of Honor, two Silver Stars, and two Purple Hearts.

[3] First Lieutenant Montgomery's official Medal of Honor citation reads: For conspicuous gallantry and intrepidity at risk of life above and beyond the call of duty on February 22, 1944, near Padiglione, Italy.

Then climbing boldly onto a little mound, he fired his rifle and threw his grenades so accurately that he killed 8 of the enemy and captured the remaining 4.

Arming himself with a carbine, he proceeded along the shallow ditch, as withering fire from the riflemen and machinegunners in the second position was concentrated on him.

His fearless, aggressive, and intrepid actions that morning, accounted for a total of 11 enemy dead, 32 prisoners, and an unknown number of wounded.