Allen Lynch was bullied throughout his school years. A loner, he was a poor student who had few friends. When he graduated from high school in 1964, he felt that he had to get away from Chicago and build a new life. He enlisted in the Army that November.

After three weeks of basic training, he was invited to attend Officer Candidate School at Fort Benning, Georgia. After four weeks he dropped out and was reassigned to a unit in Germany. A year later, he volunteered to serve in Vietnam.

Upon arriving in Vietnam in the fall of 1966, Lynch was assigned to the 12th Cavalry, where for several months he served as a rifleman, then he became his platoon's radiotelephone operator. In December 1967, his company was in the Bong Son area of the Central Highlands. The unit had been in almost daily contact with the enemy for a month and a half and on December 14, it was ordered to the rear for rest and recuperation. But another company in the battalion was ambushed, and the next morning Lynch's unit was quickly reassembled and inserted during an air assault against a large force of North Vietnamese regulars and Vietcong who were massing for the Tet Offensive, which erupted two months later.

The fighting was heavy throughout the morning. Early in the afternoon, Lynch saw three wounded soldiers out in the open who were under intense enemy fire. He dropped his radio and went to help. Despite heavy enemy fire, he reached the men and carried them one by one to a trench that offered some protection.

The Americans were separated from the enemy by a large hedgerow of bamboo. Lynch fired at the sound of the enemy's voices and over the next few hours killed several of them. Lynch's company temporarily pulled back because of the intensity of the enemy fire. Then he located counterattacking friendly forces and assisted in evacuating their wounded. He was in action for several more weeks before he was ordered to the rear. In June 1968, he was sent to Fort Hood, Texas, where he was discharged in April 1969.

One year later, one day before he was to be married, he was returning home from his job as a UPS deliveryman when he saw that he was being followed by a policeman. Lynch feared he would be receiving a ticket, but the officer handed him a note with a telephone number on it and told him to call it. When he called, he was informed that he was to receive the Medal of Honor. President Richard Nixon presented it to him on May 14, 1970. A few months later, Lynch took a job with the Veterans Administration.

Lynch graduated from Southern Illinois University with a degree in health care administration. He also completed twenty-one years of service in the Army Reserve and National Guard. In November 2005, he retired as chief of the Veterans Rights Bureau for the Illinois Attorney General. Lynch now volunteers as the chief service representative for the Illinois State Council of the Vietnam Veterans of America. He is also active in a men's Bible study and ministry at the county jail.