[6][7] Until 10 December 2011, this fixture was the most played in the history of Spanish football, when it was surpassed by El Clásico (between Real Madrid and FC Barcelona).

In that era, the caudillo General Franco used the success of Real Madrid (based in the capital city, the seat of power) as a vehicle to promote the Spanish State to foreigners,[19][20][21] whereas Athletic Bilbao – the largest club in the peripheral Basque region[22][23][24][25] whose customs and language were repressed by the central government – won no titles in the same period, only even finishing runners-up once.

[31][32][33][5] On the field, a competitive edge was briefly restored in the early 1980s when Athletic built a strong combative team that won the league twice, finishing ahead of Real Madrid by one point in 1983 with the top spot changing hands on the last day;[34] the season was nothing short of a disaster for the Meringues, who also lost in the finals of the Supercopa, the Copa del Rey (to a last-minute goal), the European Cup Winners' Cup (in extra time), and the Copa de la Liga.

[35] During a hotly-contested fixture in Bilbao in March 1990, the referee awarded a dubious penalty to the away side and had to halt the game for 12 minutes after objects were thrown at the linesman and Madrid goalkeeper Paco Buyo.

Athletic Bilbao were not among this group, now hampered by their self-imposed restrictive Basque-only player policy in an age of worldwide recruitment,[41] exemplified by Madrid's Galácticos who won eight further Champions Leagues between 1998 and 2022.

Athletic have a much lower profile and have occasionally flirted with relegation[46] (a situation observed with derision at the Santiago Bernabéu Stadium),[47] although they have consistently ranked among the top half-dozen clubs in Spain for performance,[41][48] matchday attendance[44] and popularity.

[2] The clubs' first meeting in the Supercopa de España was in 2020–21, when Athletic Bilbao defeated La Liga title holders Real Madrid in the semi-final and went on to win the trophy.

[83][84][85] Ismael Urzaiz, who played over 400 times for Athletic, started his career at Real Madrid's La Fabrica academy in the 1990s but did not make a league appearance for the club.