Ernst Franz Grünfeld (November 21 1893 – April 3 1962), an Austrian chess player and writer specializing in opening theory, was for a brief period after the First World War one of the strongest chess players in the world.
The First World War (1914–1918) seriously affected Grünfeld's chances of playing the best in the world as few tournaments were played during this troubled period. He was reduced to playing correspondence matches and spent much of his spare time studying opening variations. He started a library of chess material which he kept in his small Viennese flat until his death at the age of 68 in 1962.
He developed a reputation as an expert on openings during the 1920s and success over the board soon followed. He was 1st= in Vienna (1920) with Saviely Tartakower; 1st in Margate (1923); 1st in Merano (1924); 1st= in Budapest (1926) with Mario Monticelli; 1st in Vienna (1927) and he shared first spot in the Vienna tournaments of 1928 and 1933 (Trebitsch Memorial) — the former with Sándor Takács and the latter with Hans Müller; and finally he was 1st in the tournament at Ostrava of 1933. He also won in the 23rd DSB Congress at Frankfurt 1923.
During the Bad Pistyan tournament of April 1922 Grünfeld introduced his most important contribution to opening theory—the Grünfeld Defence. He played the defence against Friedrich Sämisch in round 7, drawing in 22 moves, and later that year he used it successfully against Alexander Alekhine in the Vienna tournament. However, he did not play the opening frequently.
During the late 1920s and 1930s Grünfeld played top board for Austria in four Chess Olympiads (1927, 1931, 1933, 1935), and his best year was in 1927 when he scored 9½/12. According to the Chessmetrics website he would have been rated around 2593 at his peak.
In May 1943, he took 2nd, behind Paul Keres, in Posen, and won in December 1943 in Vienna. After the Second World War, he tied for 3rd-4th at Vienna 1951 (Schlechter Memorial, Moshe Czerniak won). Grünfeld became an International Grandmaster in 1950. By the late 1950s he was playing very little chess and he mainly worked on his prodigious library which by now had completely filled the living room in his flat which he shared with his wife and daughter. He died in Vienna of obesity on April 3 1962.
He published several books which were generally well received and he contributed to a seminal account of the Teplice tournament of 1922. Other publications include The Queen's Pawn Game and the Queen's Gambit Declined (1924) and Taschenbuch der Eroffnungen im Schach (1953).