"leader who maintains excessive bureaucratic control," 1888, from Pooh-Bah, the name of the "Lord High Everything Else" character in Gilbert and Sullivan's "The Mikado" (1885).
A self-important person of high position and great influence. Pooh-Bah is a character in Gilbert and Sullivan's operetta The Mikado; his title is Lord-High-Everything-Else.
An important person; a self-important person; big shot, honcho, vip: where presidents and pooh-bahs commune
[1888+; fr the character in Gilbert and Sullivan's The Mikado who holds many high offices, the name probably coined fr two exclamations of contempt and derision]