One of the most dominant figures in modern chess, Botvinnik not only won the world championship three times, holding the title for a total of 13 years (1948-1957, 1958-1960, 1961-1963), but also singlehandedly revolutionized the way in which chess players studied, played and taught the game.
He introduced the rigorous study of opening theory, in which players would keep notebooks of their opponents' moves and publish analysis of their own games. He encouraged the systematic study of master games from the past and present, in order to learn from the moves they played and the differences between their individual styles. His training program included a strong emphasis on physical fitness, because he understood, ahead of his time, that the immense concentrative effort required in chess tournament play was aided by a healthy body. He also encouraged players to train in different environments, playing games under very short time constraints, in smoky or noisy rooms, and even in swimming pools.
Botvinnik's goal was to make the then Soviet Union the dominant force in chess by training an unbeatable group of young grandmasters, who would co-operate and share knowledge in what had previously been a highly individualistic game. Due to his efforts, Soviet or ex-Soviet players have almost monopolised the modern history of chess, culminating in the complete domination of the world chess scene by Garry Kasparov for 20 years from 1985-2005 (Kasparov was a student in one of Botvinnik's own chess schools, and greatly admired his style). A brief interlude, which vastly increased the popularity of chess, was provided by the American Bobby Fischer in the early 1970's when he won the title from Boris Spassky.
Botvinnik himself was not necessarily the best player in the world during the times in which he held the world title, and there were some suggestions that his opponents from the Soviet Union were encouraged to lose to him due to his influential position and political power. He also retained his title on two occasions by drawing with his opponent in number of games won, in which case the rules award the reigning champion the match. However, there is no question that he was also able to win many matches by studying his opponent in great depth, psychologically as well as in chess terms, and playing to their weaknesses.
He died in 1995, aged 84.