They traditionally face each other on Boxing Day each year[2] which usually attracts the largest NIFL Premiership attendance of the season.

Up until 1949, the big two were considered to be Linfield and Belfast Celtic as they had traditionally been the most successful teams in Northern Irish football.

This culminated with a riot on 26 December 1948 at Windsor Park that saw three Celtic players injured by Linfield supporters, including striker Jimmy Jones, who sustained a broken leg.

[5] Belfast Celtic left the Irish League at the end of the season and Glentoran became Linfield's biggest rivals.

The two teams played each other competitively for the first time in the inaugural Irish League season, with Linfield winning 7–0 at Musgrave Park on 18 October 1890, and 6–0 at Ulsterville Avenue on 21 March 1891.

In 1941, during World War II, The Oval – including terraces, offices, kits and club records – was destroyed in a bombing raid on the nearby Harland & Wolff Shipyard.

Glentoran considered leaving senior football to become a junior club, but after being lent kits from Distillery and Crusaders they continued to compete at Grosvenor.

[10] Since Belfast Celtic folded in 1949, the intensity of the Big Two rivalry has increased due to the fact that Glentoran has been the only club that has generated a support base similar in size to Linfield's, and because a number of Belfast Celtic fans started to support Glentoran due to the dissolution of their club.

[12] The BBC and Ulster Television were ordered to give police footage they had filmed of the game after nine fans were charged with the violence.

Linfield and Glentoran have been the two most successful clubs in Northern Irish football to date, regularly being the two main contenders for the major domestic honours.

In 1984, the IFA signed a 104-year agreement with Linfield to host internationals at Windsor Park, with only Glentoran objecting to the deal at the time.

This became financially lucrative for Linfield after the IFA signed a £10 million deal with Sky to televise internationals.

This necessitated redevelopment, with the Northern Ireland government funding the majority of the £36 million project to rebuild the stadium.