The Orioles first manager was their shortstop, Henry Myers. Myers managed the team for only one season, 1882, and led them to a record of 19 wins and 54 losses, for a winning percentage of .260. In 1883, Myers was replaced by Billy Barnie, who managed the team throughout the remainder of its time in the American Association, through 1891. Barnie managed the Orioles to a record of 470 wins and 548 lossess, for a .462 winning percentage. The 1050 games Barnie managed were the most in Orioles' history, and the 548 games he lost were also the most in Orioles' history.
In 1892, the Orioles joined the National League and outfielderGeorge Van Haltren became the team's manager. Van Haltren lasted only eleven games as manager, winning just one. Van Haltren's winning percentage of .091 is the lowest in Orioles' history. He was by John Waltz, who won just two of the eight games he managed. The third manager the Orioles employed in 1892 was outfielder Ned Hanlon. Hanlon managed the team through the 1898 season, leading the Orioles to three consecutive National League pennants in 1894, 1895 and 1896. In all, Hanlon managed the team for 946 games, winning 555, the most in Orioles history. His .601 winning percentage is also the highest of any Orioles manager.