The 1951 World Chess Championship was played between Mikhail Botvinnik and David Bronstein in Moscow from March 15 to May 11, 1951. It was the first match played under the supervision of FIDE; and the first to use a qualifying system of an Interzonal and Candidates Tournament to choose a challenger - a system which stayed in place until 1993.
Botvinnik was the defending champion: he was 39 years old, had been a world leading player in the 1930s and World Champion since 1948. The challenger, David Bronstein, was 27 years old and relatively new to top-level competition.
The match ended in a 12–12 tie (5 wins each, and 14 draws), meaning Botvinnik retained the title of World Champion. Writing in 1973, Israel Horowitz described the match as "perhaps the most interesting match ever played for the world championship".
1948 Interzonal tournament
An interzonal tournament was held at Saltsjöbaden in Stockholm, Sweden, in July and August 1948. The top eight finishers qualified for the Candidates tournament.
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The four players tied for sixth place were to have played off for three spots in the Candidates tournament, but Bondarevsky had to withdraw due to illness, so the other three qualified automatically.
1950 Candidates tournament
The 1950 Candidates tournament was held in Budapest, Hungary in April and May 1950. The players who finished second through fifth in the 1948 championship tournament (Smyslov, Keres, Reshevsky, and Euwe) were seeded directly into the tournament, along with Reuben Fine, who had been invited to the 1948 tournament but declined, and the top eight finishers from the Interzonal.