Peel had been a constant presence at Radio 1 from its birth in 1967, and had been responsible for bringing listeners a stream of new music throughout his career. He had also managed to successfully cross over to Radio 4 as a presenter of 'Home Truths', which he fronted since 1998, the same year as he received his OBE.
His presence at Radio 1 brought a stream of musicians through his doors to record live sessions, from Blur to Nirvana, New Order, Billy Bragg and PJ Harvey.
The news of his untimely death was followed by several tributes from within the BBC, led by Radio 1 controller Andy Parfitt.
"John Peel was a broadcasting legend. I am deeply saddened by his death, as are all who work at Radio 1," Parfitt said.
"John's influence has towered over the development of popular music for nearly four decades and his contribution to modern music and music culture is immeasurable. Hopeful bands all over the world sent their demo tapes to John, knowing that he really cared. His commitment and passion for new music only grew stronger over the years.
"In fact, when I last saw him he was engaged in a lively debate with his fellow DJs over the state of new music today. He will be hugely missed."
BBC director of radio and music Jenny Abramsky said that Peel was a unique broadcaster whose influence on Radio 1 could be felt from its very first days.
"His open-minded approach to music was mirrored by his equally generous approach to his audience when he went to Radio 4 to present 'Home Truths'. He had a remarkable rapport with all his listeners. John is simply irreplaceable. Our hearts go out to Sheila and his children."
Peel also appeared often on TV, with his most recent appearances including the BBC's coverage of the Glastonbury Festival, as well as BBC Two's 'Grumpy Old Men' and 'Room 101'.
Mark Thompson, BBC Director-General, said: "We are all very shocked and saddened by the news of John's death.
"He was one of the giants of radio and will be missed, not just by everyone at the BBC, but by millions of listeners of all ages."
John Peel biography
John Peel was born in Chester in 1939.
At the age of 23 he moved to Texas where he worked for WRR Radio in Dallas. He was in Dallas when both John F Kennedy and Lee Harvey Oswald were shot.
He returned to the UK in 1967 and joined Radio London with the celebrated show 'The Perfumed Garden'.
Peel joined Radio 1 in 1967 establishing himself with the late night programme 'Top Gear'.
His career really took off at the BBC and he became the first DJ to give exposure to alternative music genres such as punk, reggae and hip-hop before they crossed over to mainstream.
Before long, Peel was considered the most popular UK DJ, regularly topping music paper Best DJ polls and winning the Sony award for Broadcaster of the Year. In 1995, NME crowned him the 'Godlike Genius' at its annual awards event.
He is credited with launching the careers of The Fall, the Undertones, and Pulp, among many others.
Peel calmed down in his later years where he steered clear of punk rock to present 'Home Truths' on BBC Radio 4.
Peel recently celebrated 40 years on the air and continued to seek out the best new music around.
He lived in Suffolk with his wife Sheila, who he affectionately called "The Pig".
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