Alfred Martin 'Jack' Harris was born at Mildura and grew up at nearby Buronga, on the banks of the Murray River. He received little formal education, but later joined the Australian Army, where he became proficient in Japanese and Chinese. In 1950, he briefly served with the 3rd Battalion RAR during the Allied occupation of Japan. Then in 1953 he served in Korea in an intelligence unit, where he was wounded in action (he was subsequently awarded the Military Medal).