UEFA European Championship - Wikipedia
https://en.wikipedia.org/wiki/UEFA_European_ChampionshipBefore 1980, only four teams qualified for the final tournament. From 1980, eight teams competed. In 1996 the tournament expanded to 16 teams, since it was easier for European nations to qualify for the World Cup than their own continental championship; 14 of the 24 teams at the 1982, 1986 and 1990 World Cups had been European, whereas the European Championship finals still involved only eight te…
UEFA coefficient - Wikipedia
https://en.wikipedia.org/wiki/UEFA_coefficientThe association coefficient is used to rank the football associations of Europe, and thus determine the number of clubs from an association that will participate in the UEFA Champions League, the UEFA Europa League and the UEFA Europa Conference League. The UEFA ranking determines the number of teams competing in the season aft…