Guy Lombardo and his Royal Canadians made Auld Lang Syne a North American New Year's Eve tradition through radio broadcasts.
Lombardo's orchestra was known for its annual New Year's Eve performances, especially broadcasts from New York City. The band's gentle dance-band arrangement of Auld Lang Syne became strongly associated with the moment after midnight, helping turn a Scottish song into a familiar North American year-end ritual.
The Royal Canadians first performed the song on a New Year's Eve broadcast in the 1920s, and Lombardo continued to feature it for decades. His broadcasts were a major part of holiday listening before television became dominant, giving the song a recurring place in domestic celebrations.
Lombardo did not write Auld Lang Syne. The words are associated with Robert Burns, and the song already had Scottish roots before Lombardo popularized his arrangement. The orchestra's importance was cultural and broadcast-related: it helped standardize the song's New Year's association for a mass audience.