Though the Bills and Dolphins both originated in the American Football League, the Dolphins did not start playing until 1966 as an expansion team while the Bills were one of the original eight teams. The rivalry first gained prominence when the Dolphins won every match-up against the Bills in the 1970s for an NFL-record 20 straight wins against a single opponent (the Bills defeated the Dolphins in their first matchup of the 1980s).
Though both teams originated in the American Football League, the Dolphins did not begin playing until 1966 as an expansion team while the Bills were one of the original eight teams. The rivalry gained prominence when the Dolphins won every match-up against the Bills in the 1970s for a record 20 straight wins against a single opponent (the Bills defeated the Dolphins in their first matchup of the 1980s).