Don was born in Washington, Indiana, on the 26th of August, 1918. His father was Brigadier General Don Faith that had served with the Army during World War 1 and when Don Jr tried to enroll with the US Military Academy, he was found medically unfit for admission. He was then drafted for World War 2 but his physical was rejected for the same reason that the Military Academy had disqualified him. He was able to appeal the disqualification and once he graduated from Georgetown University on the 25th of June, 1941, Don was allowed to join. He completed Officer Candidate School on the 26th of February, 1942 and received his commission. Don was then assigned to the 82nd Airborne Division for the remainder of the war and served as a staff officer and as an aid to Brigadier General Matthew Ridgway. He also participated in all of the division's combat jumps in North Africa, Italy, France, Holland, and Germany.

After World War 2, Don was assigned to duty in China and then to Japan with the 7thInfantry Division. By then, he was a Lieutenant Colonel and a battalion commander and the division was deployed to Korea to help stop the invasion of South Korea. When the commander of the 31st Regimental Combat Team, Colonel Allan MacLean, was killed on the 1st of December, Don took command of the entire regiment and it was his actions that same day when leading an attack against a roadblock that would cost him his life and earn him the Medal of Honor. The citation reads:

The President of the United States of America, in the name of Congress, takes pride in presenting the Medal of Honor (Posthumously) to Lieutenant Colonel (Infantry) Don Carlos Faith Jr. (ASN: O-46673), United States Army, for conspicuous gallantry and intrepidity in action above and beyond the call of duty while Commanding the 1st Battalion, 32d Infantry Regiment, 7th Infantry Division, in action against enemy aggressor forces at Hagaru-ri, (Chosin Reservoir) North Korea, from 27 November to 1 December 1950. When the enemy launched a fanatical attack against his battalion, Lieutenant Colonel Faith unhesitatingly exposed himself to heavy enemy fire as he moved about directing the action. When the enemy penetrated the positions, Lieutenant Colonel Faith personally led counterattacks to restore the position. During an attack by his battalion to effect a junction with another U.S. unit, Lieutenant Colonel Faith reconnoitered the route for, and personally directed, the first elements of his command across the ice-covered reservoir and then directed the movement of his vehicles which were loaded with wounded until all of his command had passed through the enemy fire. Having completed this he crossed the reservoir himself. Assuming command of the force his unit had joined he was given the mission of attacking to join friendly elements to the south. Lieutenant Colonel Faith, although physically exhausted in the bitter cold, organized and launched an attack which was soon stopped by enemy fire. He ran forward under enemy small-arms and automatic weapons fire, got his men on their feet and personally led the fire attack as it blasted its way through the enemy ring. As they came to a hairpin curve, enemy fire from a roadblock again pinned the column down. Lieutenant Colonel Faith organized a group of men and directed their attack on the enemy positions on the right flank. He then placed himself at the head of another group of men and in the face of direct enemy fire led an attack on the enemy roadblock, firing his pistol and throwing grenades. When he had reached a position approximately 30 yards from the roadblock he was mortally wounded, but continued to direct the attack until the roadblock was overrun. Throughout the five days of action Lieutenant Colonel Faith gave no thought to his safety and did not spare himself. His presence each time in the position of greatest danger was an inspiration to his men. Also, the damage he personally inflicted firing from his position at the head of his men was of material assistance on several occasions. Lieutenant Colonel Faith's outstanding gallantry and noble self-sacrifice above and beyond the call of duty reflect the highest honor on him and are in keeping with the highest traditions of the U.S. Army.

Don was listed as missing in action and the only reason the account of this story exists is because the driver of the truck was able to escape back to the United Nations lines. General Omar Bradley, the then chairman of the Joint Chiefs of Staff, posthumously awarded the Medal of Honor to Don's wife, Barbara, in a ceremony in Washington DC on the 21st of June, 1951. Don's classification was listed as Killed in Action Body not Recovered for 62 years. On the 11th of October, 2012, Don's remains were recovered and identified via DNA testing by a field recovery team with the Joint Prisoners of War, Missing in Action Accounting Command. Six months later, he returned to the States and Don Carlos Faith Jr was buried in Arlington National Cemetery on the 17th of April, 2013: Section 4, Grave 3016.