When Acting Captain Humphrey Lyttelton of the Grenadier Guards stormed ashore during the Allied invasion of Italy in 1943, he held a pistol in one hand. In the other, he carried a small bag containing a trumpet.
If proof were needed of the unbreakable bond between the 86-year-old Old Etonian known to his myriad fans as "Humph" and the jazz music he has played for at least an hour a day since he was a teenager, then it was provided 65 years ago on the beachhead at Salerno under a barrage of German artillery.
Once he had shepherded his men to safety, he unwrapped his instrument and played "something celebratory" before complaining that "there wasn't really much time for music".
The sage of British jazz and oft-declared national treasure for his deadpan wit has since made up for that. The BBC yesterday announced that he will broadcast the last of his The Best of Jazz programmes on Radio 2 after 40 years – during which time he has brought every possible aspect of the foot-tapping genre to millions.
The show will consist of a Desert Island Discs-style rundown of 10 jazz records that represent landmarks in Lyttelton's remarkable life. He said: "I think it's time to clear a space for some of my other ambitions."
Although perhaps better known as the faux-lethargic chairman of I'm Sorry I Haven't A Clue, BBC Radio 4's panel quiz show with a legendary line in smutty double entendres from its host, Lyttelton has dedicated much of his time to music. He has also worked as a newspaper cartoonist, biographer, President of The Society for Italic Handwriting and some-time fag for Lord Carrington, the former Conservative foreign secretary and secretary general of Nato.
Born as one of five children to an Eton house master and aristocratic mother, Humphrey defied what he describes as his "land-owning, political, military, clerical and scholastic forebears" to become a jazz obsessive and, after the war, dedicated himself to reviving British traditional jazz.
In 1956, his composition "Bad Penny Blues" became the first jazz record to reach the British Top 20 and, alongside Chris Barber and Ken Colyer, he attracted the attention of some legendary figures. After playing the first International Jazz Festival in Nice in 1948, Louis Armstrong remarked: "That boy's coming on." Later on, Satchmo famously described Lyttelton as "that cat in England who swings his ass off".
Playing a version of New Orleans jazz, his American fans believed he would go far. Buck Clayton, the trumpeter for Count Basie, said: "If Humph had been an American, he would have been compared with the greatest."
Instead, Lyttelton chose to navigate a path between the rival factions of British jazz, moving from the "trad" genre to a broader format, uniting styles considered sacrosanct with his eight-piece Humphrey Lyttelton Band, which continues to hold regular sell-out concerts to this day.
Jazz experts said yesterday that Lyttelton was a rare combination of accomplished musician and ambassador for his art form.
Johnny Dankworth, the leading British saxophonist and clarinettist, said: "When Humph and I first started, there was almost a gang culture in jazz. You either belonged to trad or bebop and there was nothing in the middle. At my end, we wore sharp suits, white shirts and black ties. At Humph's end, they would sit in rhythm clubs, discussing music and smoking filthy pipes. But what Humph did was to bring the different elements together.
"He has been a great campaigner for making jazz broader. Whenever I heard the The Best of Jazz, I never knew what sort of record I was going to hear and always knew I was going to learn something I didn't know because of what Humph tells you."
It should all have been very different. As the grandson of the 8th Viscount Cobham, Lyttelton was born into a rarefied world of privilege as well as intellectual and physical rigour.
Describing how he felt unable to run despite being shot at by a sniper, he once said: "This had nothing to do with courage or coolness in the face of danger. It is just my training at Eton and in the Guards had instilled in me a notion that to run is somehow undignified. I believe I was actually afraid of being laughed at by the sniper."
As a young man he was sent to experience life in the steelworks of Port Talbot in South Wales with a view to a potential career as a captain of industry. Instead he became a lifelong Labour Party member deeply averse to the pomp and circumstance of his upbringing.
He credits his love of music to his mother, Pamela, who took him to buy his first trumpet at the age of 15 on London's Charing Cross Road when both were meant to be watching the annual cricket match at Lord's between Eton and Harrow.
Lyttelton, who guards his privacy so closely that not even his band members or contestants on I'm Sorry I Haven't A Clue are allowed to have his phone number, held out the possibility that he would continue to make one-off contributions to the BBC's jazz coverage.
He said: "I have had a great relationship with Radio 2 and my listeners and will perhaps pop in to make further contributions as the occasions arise. Meanwhile, 'au revoir'."
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