William Henry Greason (born September 3, 1924) is an American former professional baseball player who later became a Baptist minister. He was born in Atlanta. Greason enlisted in the United States Marine Corps during World War II and did his basic training at Montford Point. He embarked with the 66th Supply Platoon, an all-black unit, in the Pacific Theater of Operations and took part in the Battle of Iwo Jima.