A political and musical radical, with a lifelong commitment to music education, he rose to become Queen Elizabeth II's official composer between 2004 and 2014.
His appointment caused a stir as he was a republican at the time, although he said later that he had come to appreciate the "continuity, tradition and stability" of the monarchy.
Maxwell Davies was a prolific composer, and his works included ten symphonies and six operas. He was also composer/conductor with both the Royal Philharmonic and the BBC Philharmonic Orchestras.
His last work, children's opera "The Hogboon", is due to premiere at the Barbican in London in June, performed by the London Symphony Orchestra conducted by Simon Rattle.
Born in Salford in England, in 1971 he moved to the Orkney Islands, an archipelago off the northeast coast of Scotland. The landscape and culture there informed many of his works.
Maxwell Davies was knighted in 1987 and earlier this year the Royal Philharmonic Society gave awarded him its gold medal, one of the highest honours in British classical music.
"Over six decades he has been part of our public consciousness; an extraordinary musician who has moved from iconoclast and enfant terrible of the avant garde, to a leading cultural figure," it said at the time.
Maxwell Davies was diagnosed with an aggressive form of leukaemia in 2013. Classical music agency Intermusica announced his death, describing him as "one of the foremost composers of our time".
"Max was a truly unique musician. A remarkable composer who created music theatre works of searing power, great symphonies, intense chamber music, works of truly universal popularity," said his friend Sally Groves, former creative director of publishers Schott Music.
"A fierce fighter for music in the community and in education, and on environmental issues. And a man of invincible integrity, a true friend and a teller of truth to power."
Maxwell Davies made headlines in 2005 when police found the body of a swan, a protected species, at his house. He said the bird died after hitting a power line.
Describing the moment the police arrived, he said: "I offered them coffee and asked them if they would like to try some swan terrine but I think they were rather horrified. That was a mistake, wasn't it?"
