A native of Minooka, Pennsylvania, O'Neill was one of four brothers who escaped a life in the coal mines by playing in the major leagues. The others were Jack, a catcher in the National League (1902-06); Mike, a righthanded pitcher in the NL (1901-04, 1907); and Jim, an infielder with the American League Washington Senators (1920, 1923). To top it off, two of Steve O'Neill’s daughters married baseball players, one of whom was Skeeter Webb, who worked for O'Neill when he managed the Detroit Tigers during the 1940s.

Steve had by far the most successful baseball career of the O'Neill brothers. He was a catcher for 17 years in the AL, with the Cleveland Indians (1911-23), Boston Red Sox (1924), New York Yankees (1925), and St. Louis Browns (1927-28). His playing career curtailed by an injury sustained in a car accident, O'Neill compiled a batting average of .263 in 1,586 games, and, in his only World Series appearance in 1920, hit .333 in seven games as the backstop for the World champion Indians.

As a major league manager with four teams - the Indians (1935-37), Tigers (1943-48), Red Sox (1950-51) and Philadelphia Phillies (1952-54) - O'Neill never had a losing record. His Tigers won the 1945 World Series (when they defeated the Chicago Cubs in the Cubs’ last Fall Classic appearance) and O’Neill was known for turning around under-performing teams, often in mid-season. His career winning percentage over 14 seasons was a stalwart .559. He also served as a coach for Cleveland, Detroit and Boston.

O'Neill died at age 70 in Cleveland, Ohio, after suffering a heart attack.