Boris Vasilievich Spassky is a Russian and former Soviet chess grandmaster who was the tenth World Chess Champion, holding the title from 1969 to 1972. Spassky played three world championship matches: he lost to Tigran Petrosian in 1966; defeated Petrosian in 1969 to become world champion; then lost to Bobby Fischer in a famous match in 1972.
Tigran Vardani Petrosian was a Soviet-Armenian chess grandmaster and the ninth World Chess Champion from 1963 to 1969. He was nicknamed "Iron Tigran" due to his almost-impenetrable defensive playing style, which emphasized safety above all else. Petrosian is often credited with popularizing chess in Armenia.
Mikhail Nekhemyevich Tal was a Soviet and Latvian chess player and the eighth World Chess Champion. He is considered a creative genius and is widely regarded as one of the most influential players in chess history. Tal played in an attacking and daring combinatorial style. His play was known above all for improvisation and unpredictability. Vladislav Zubok said of him, "Every game for him was as inimitable and invaluable as a poem".
Leonid Zakharovych Stein was a Soviet chess Grandmaster from Ukraine. He won three USSR Chess Championships in the 1960s, and was among the world's top ten players during that era.
Jørgen Bent Larsen was a Danish chess grandmaster and author. Known for his imaginative and unorthodox style of play, he was the second-strongest non-Soviet player, behind only Bobby Fischer, for much of the 1960s and 1970s. He is considered to be the strongest player born in Denmark and the strongest from Scandinavia until the emergence of Magnus Carlsen.
Samuel Herman Reshevsky was a Polish chess prodigy and later a leading American chess grandmaster. He was a contender for the World Chess Championship from the mid-1930s to the mid-1960s: he tied for third place in the 1948 World Chess Championship tournament, and tied for second in the 1953 Candidates tournament. He was an eight-time winner of the US Chess Championship, tying him with Bobby Fischer for the all-time record.
Robert Eugene Byrne was an American chess player and chess author who held the FIDE title of Grandmaster (GM). He won the U.S. Championship in 1972, and was a World Chess Championship Candidate in 1974. Byrne represented the United States nine times in Chess Olympiads from 1952 to 1976 and won seven medals. He was the chess columnist from 1972 to 2006 for The New York Times, which ran his final column on November 12, 2006. Byrne worked as a university professor for many years, before becoming a chess professional in the early 1970s.
Oscar Roberto Panno is an Argentine chess Grandmaster.
Efim Petrovich Geller was a Soviet chess player and world-class grandmaster at his peak. He won the Soviet Championship twice and was a Candidate for the World Championship on six occasions. He won four Ukrainian SSR Championship titles and shared first in the 1991 World Seniors' Championship, winning the title outright in 1992. His wife Oksana was a ballet dancer while his son Alexander was also a chess master. Geller was coach to World Champions Boris Spassky and Anatoly Karpov. He was also an author.
Lajos Portisch is a Hungarian chess Grandmaster, whose positional style earned him the nickname, the "Hungarian Botvinnik". One of the strongest non-Soviet players from the early 1960s into the late 1980s, he participated in twelve consecutive Interzonals from 1962 through 1993, qualifying for the World Chess Championship Candidates Cycle a total of eight times. Portisch set several all-time records in Chess Olympiads. In Hungarian Chess Championships, he either shared the title or won it outright a total of eight times. He won many strong international tournaments during his career. In 2004, Portisch was awarded the title of 'Nemzet Sportolója', Hungary's highest national sports achievement award.
Robert James Fischer was an American chess grandmaster and the eleventh World Chess Champion. A chess prodigy, he won his first of a record eight US Championships at the age of 14. In 1964, he won with an 11–0 score, the only perfect score in the history of the tournament. Qualifying for the 1972 World Championship, Fischer swept matches with Mark Taimanov and Bent Larsen by 6–0 scores. After winning another qualifying match against Tigran Petrosian, Fischer won the title match against Boris Spassky of the USSR, in Reykjavík, Iceland. Publicized as a Cold War confrontation between the US and USSR, the match attracted more worldwide interest than any chess championship before or since.
Borislav Ivkov was a Serbian chess Grandmaster. He was a World championship candidate in 1965, and played in four more Interzonal tournaments, in 1967, 1970, 1973, and 1979.
At the World Chess Championship 1963, Tigran Petrosian narrowly qualified to challenge Mikhail Botvinnik for the World Chess Championship, and then won the match to become the ninth World Chess Champion. The cycle is particularly remembered for the controversy surrounding the Candidates' Tournament at Curaçao in 1962, which resulted in FIDE changing the format of the Candidates Tournament to a series of knockout matches.
The Piatigorsky Cup was a triennial series of double round-robin grandmaster chess tournaments held in the United States in the 1960s. Sponsored by the Piatigorsky Foundation, only two events were held, in 1963 and 1966. The Piatigorsky Cups were the strongest U.S. chess tournaments since New York 1927.
A World Chess Championship was played between Tigran Petrosian and Boris Spassky in Moscow from April 9 to June 9, 1966. Petrosian won.
The 1975 World Chess Championship was not played due to a dispute over the match format. Champion Bobby Fischer was to play Anatoly Karpov in Manila, commencing June 1, 1975. Fischer refused to play the then-standard "Best of 24 games" match and, after FIDE was unable to work out a compromise, forfeited his title instead. Karpov was named World Champion by default on April 3, 1975.
Viktor Lvovich Korchnoi was a Soviet and Swiss chess grandmaster (GM) and chess writer. He is considered one of the strongest players never to have become World Chess Champion.
Tigran Petrosian 
