Efim Dmitriyevich Bogoljubow (Russian: Ефим Дмитриевич Боголюбов April 14, 1889 – June 18, 1952) was a Russian-born German chess grandmaster known for his versatility and ability to adapt to different situations. He was one of the world's leading players in the 1920s and 1930s, during the development of modern chess strategy.
Bogoljubow represented Russia in four Chess Olympiads and later the German team in five Olympiads. He won two of the Olympiads, one of them for Germany. He also held the FIDE title of International Grandmaster, won several international tournaments, and had an illustrious career as a chess writer.
His early successes in chess started in Kiev where he moved after the end of the First World War. From 1925 to 1941, he was champion of Germany eight times which is the record till now.
He participated in two matches for the World Chess Championship against Alexander Alekhine, both times losing. However, he was also successful in several strong international tournaments, twice winning the prestigious Hastings International Chess Congress.
In the chess community, Bogoljubow is remembered for his chess aphorism "When I am White, I win because I am White; when I am Black, I win because I am Bogoljubow."
Bogoljubow's contribution to chess opening theory includes the Bogoljubow Indian Defence (1.d4 Nf6 2.c4 e6 3.Nf3 Bb4+) and variations in the Nimzo-Indian and Grunfeld defences.
Away from the chessboard, Bogoljubow was known for his good-natured personality. He died in Triberg im Schwarzwald, Germany on June 18, 1952. His life and work have been the subject of a number of books and articles.