nWo (New World Order)
The New World Order started at Bash at the Beach on July 7, 1996, when Hulk Hogan turned heel and joined Scott Hall and Kevin Nash. The three presented themselves as an outside force invading WCW rather than a normal stable, and the angle ran until the company closed in 2001.
Members
Exact join dates for the secondary members varied as the group expanded.
Why it mattered
The nWo blurred the line between show and reality by presenting Hall and Nash as an outside invasion rather than contracted WCW wrestlers. The uncertainty over who might join next kept the story unpredictable for years.
The angle also drove business. It pushed WCW Nitro past WWF Raw for 83 straight weeks in the Monday Night War, and its template of a growing renegade group changed how factions have been booked ever since.