Elgar's "Pomp and Circumstance" marches have been Proms favourites for years. And this summer, more than 70 years after his death, the premiere of a new one is likely to be a high point of the Proms festival.
The composer Anthony Payne has taken surviving fragments prepared for a sixth march and finished it, just as he did with Elgar's Third Symphony nine years ago.
As befits a work started in Elgar's last years, it is very different in spirit from the Pomp and Circumstance March No 1, better known as Land of Hope and Glory. Nicholas Kenyon, the Proms controller who unveiled the 112th season of concerts yesterday, said: "This hasn't come out at all like Land of Hope and Glory. It's not exuberant, it's slightly more sombre and has a wistful quality. [Payne] has had to deploy his in-depth knowledge of Elgar's style to achieve this. He has said 'It's Elgar's material but my working out'."
"No 6" has been created from a few small sketches by Elgar made in the 1930s, which survived among papers at the British Library and the Royal School of Church Music. Elgar, who died in 1934, noted that they were "jolly good".
Although the finished piece has not been performed by an orchestra, Mr Kenyon has heard a synthesised version. "I thought it was extremely beautiful, but quite surprising. It has an autumnal quality." He added: "At the end of his life, Elgar started on quite a few projects, but he just seemed to have lost the will to compose. He composed very little after his wife died [in 1920, when he was 63]."
The work will not be the only completion project on offer at this year's Proms, which run from 14 July to 9 September and include 90 concerts - the most ever - plus assorted associated events.
Among a number of concerts marking the 250th anniversary of the birth of Mozart will be the British premiere of his Mass in C minor, which has been completed by the American Robert D Levin. The work was apparently started as a gift for his wife, Constanze, but never finished.
The Mozart celebration also includes a production of his opera Cosi fan tutte from Glyndebourne.
The other composer honoured this year will be Shostakovich, who was born a century ago. Valery Gergiev will conduct a concert version of the Russian's opera Lady Macbeth of Mtsensk.
Mr Kenyon said Shostakovich's stock had risen in the decade he had run the Proms. "Shostakovich is the single composer who has zoomed up the order in terms of audience reaction and audience response," he said.
Other highlights include a performance of Wagner's opera Siegfried, and appearances by American orchestras, including the Philadelphia and Pittsburgh, alongside European ensembles including the Berlin Philharmonic with Sir Simon Rattle.
The Peruvian tenor Juan Diego Florez, a rising star, will make his Proms debut, as will an 83-year-old world music legend, Cheikha Rimitti from Algeria.
Three years after her last visit, the Queen will return for a special Prom for her 80th birthday.
The Last Night will be conducted by Mark Elder, 16 years after the BBC dropped him as maestro for the finale after he suggested he would not be able to conduct such a nationalistic evening if Britain were at war. Nicholas Kenyon said the Last Night had changed into an "inclusive celebration of music-making around the UK" and Elder had been delighted to accept.
The Proms will cost £8.5m to stage this year, of which £3.7m should be recouped in ticket sales. Prices range from £5 for the Prommers, who stand, to £42.
Many of the concerts will be broadcast on television, including the last three weeks live on BBC 4, and all of them will be transmitted on Radio 3.Reuse content