Celtic and Rangers are the two most successful teams in the Scottish football league with the two sides taking 1st and 2nd place in the league every season between 1995/96 and 2005/6.

The rivalry is one of the oldest in football dating back to 1888. But the Old Firm derby is also inexorably linked to religion. Celtic is a Catholic club while Rangers is Protestant and the issue of sectarianism is a continuing undercurrent throughout the entire rivalry.