Richard was born in New York City on the 28th of August, 1897, and he had a brief professional boxing career, winning twelve fights. At the age of eighteen, Richard enlisted in the New York Army National Guard in 1916 and he served with the 69th Infantry Regiment in Texas during the Pancho Villa Expedition in support of the Mexican Revolution. The 69th Infantry Regiment was re-designated as the 165th Infantry when they were deployed to Europe during World War 1 and it was Richard's actions as a Sergeant leading a reconnaissance mission in France that would earn him the Medal of Honor. The citation reads:
In advance of an assaulting line, he attacked a detachment of about 25 of the enemy. In the ensuing hand-to-hand encounter he sustained pistol wounds, but heroically continued in the advance, during which he received additional wounds: but, with great physical effort, he remained in active command of his detachment. Being again wounded, he was forced by weakness and loss of blood to be evacuated, but insisted upon being taken first to the battalion commander in order to transmit to him valuable information relative to enemy positions and the disposition of our men.
Because of the information Richard brought back, US troops were able to destroy the German artillery and he was then hospitalized for his wounds but then left the hospital in order to rejoin his unit, against doctor's orders. He continued to serve until he was wounded again and he remained in the hospital, this time in the States and until after the end of the War. Richard refused recommendations to amputate his legs and was able to eventually walk unaided. In 1921, while recuperating in Fordham Hospital in the Bronx, Richard received the Medal of Honor for his actions from Ferdinand Foch, Supreme Allied Commander during the War, in a ceremony in nearby Fordham University. Richard also was commissioned to Second Lieutenant and his time in service ended two years later.
Richard went on to attended courses in construction at the City College of New York and during the construction of the George Washington Bridge, he worked as a concrete pourer. He also worked in sales and purchased a liquor store, while also giving speeches on behalf of New York Republican candidates during fundraiser dinners and other events. Richard was also active in organizations such as the Catholic War Veterans, Disabled American Veterans, Veterans of Foreign Wars, and the American Legion, going to to serve as the Executive Director of the Congressional Medal of Honor Society. During World War 2, he was employed by the Office of Strategic Service, the predecessor to the Central Intelligence Agency, to help investigate potential German spies New England and New York. The head of the OSS, William Donovan, had been Richard's commander during World War 1.
Richard married Estelle Johnson in 1921 and they had one son, William, who would go on to serve in the US Army during World War 2. His sister married Richard's First Sergeant, Edward Geaney, who received the Distinguished Service Cross for actions during the same time as Richard and he received his DSC during the same ceremony as Richard's Medal of Honor. Richard William O'Neill died at the age of 84 on the 9th of April, 1982, in a nursing home in Valhalla, New York. He is buried in the Gate of Heaven Cemetery in Hawthrone, New York: Section 22, Plot 488, Grave 19. His wife joined him three years later.