Netherlands Eredivisie

From the foundation of the Dutch national football championship in 1898 until 1954, the title was decided through play-offs by a handful of clubs who had previously won their regional league. The competition was purely an amateur one; the Royal Dutch Football Association (KNVB) rejected any form of payment and suspended players who were caught receiving salary or transfer fees. The call for professional football grew in the early fifties after many national team members left to play abroad in search for financial benefits. The KNVB would usually suspend these players, preventing them from appearing for the Dutch national team. After the North Sea flood of 1953, the Dutch players abroad (mainly playing in the French league) organised a charity match against the France national team in Paris. The match was boycotted by the KNVB, but after the assembled Dutch players defeated the French (2–1), the Dutch public witnessed the heights that could be achieved through professional football. To serve the growing interest, a dissident professional football association (the NBVB) and league were founded for the 1954–55 season. On 3 July 1954, the KNVB met with a group of concerned amateur club chairmen, who feared the best players would join the professional teams. The meeting, dubbed the slaapkamerconferentie ('bedroom conference'), led to the Association reluctantly accepting semi-professionalism.

Meanwhile, both the KNVB and the NBVB started their separate competition. The first professional football match was contested between Alkmaar and Venlo. The leagues went on for eleven rounds, before a merger was negotiated between the two federations in November. Both leagues were cancelled and a new, combined competition emerged immediately. De Graafschap, Amsterdam, Alkmaar and Fortuna '54 from the NBVB were accepted to the new league. Other clubs merged, which led to new names like Rapid J.C., Holland Sport and Roda Sport. The first (semi-)professional league was won by Willem II. For the 1956–57 season, the KNVB abandoned the regional league system. The Eredivisie was founded, in which the eighteen best clubs nationwide directly played for the league title without play-offs. The inaugural members of the Eredivisie in 1956 were Ajax, BVC, BVV, DOS, EVV, Elinkwijk, SC Enschede, Feijenoord, Fortuna '54, GVAV, MVV, NAC, NOAD, PSV, Rapid J.C., Sparta, VVV '03 and Willem II. Ajax was the first team to claim the title that season. Below is a complete record of how many teams played in each season throughout the league's history;

• 18 clubs: 1956–1962
• 16 clubs: 1962–1966
• 18 clubs: 1966–present