William J. O'Brien

William Joseph O'Brien (September 25, 1899 - July 7, 1944) was a United States Army officer and a recipient of the United States military's highest decoration—the Medal of Honor—for his actions in World War II during the Battle of Saipan.

Biography O'Brien joined the Army from his birth city of Troy, New York, and by June 20, 1944, was serving as a lieutenant colonel in the 1st Battalion, 105th Infantry Regiment, 27th Infantry Division. On that day, on Saipan in the Marianas Islands, he braved enemy fire to reach several American tanks which were unknowingly firing on their own troops. The next week, on June 28, he oversaw and personally led an attack on a Japanese held ridge. On July 7 his battalion came under attack from a much larger enemy force, the largest banzai charge of the Pacific War. He refused to leave the front lines even after being wounded and continued to rally his men until being overrun and killed. He was posthumously awarded the Medal of Honor on May 9, 1945, for his actions throughout the battle for Saipan.