John O'Neill
Many noteworthy people have had the name John O'Neill
- In 1866, one John O'Neill led 800 Fenian raiders across the Niagara River at Buffalo, New York/Fort Erie, Ontario, as part of an effort to free Ireland from the English as part of the Fenian Invasion of Canada.
- In 1971, a Vietnam War veteran named John O'Neill debated John Kerry (who later became a candidate in the 2004 presidential election) on The Dick Cavett Show. O'Neill later helped to form the anti-Kerry group Swift Boat Veterans for Truth.
- John P. O'Neill (1952–September 11, 2001) was an FBI agent who investigated terrorism and Al Qaeda in the late 1990s. He left the bureau and became head of security at the World Trade Center shortly before to the September 11, 2001 attacks.
- Another John O'Neill is the head of the Australian Soccer Association.