In the Court of the Crimson King is the debut album of the British progressive rock band King Crimson, released on October 10, 1969. The album is considered one of the strongest in the progressive rock genre, as King Crimson went far beyond the boundaries of blues-based rock music, introducing elements of jazz and symphonic classical music. The album has been praised by critics and musicians alike and is considered one of the most influential progressive rock albums ever released.