Elgar was right when he said he had a tune that 'would knock em, knock em flat'.
He set it within his first Pomp and Circumstance March, and it was an instant hit at its 1901 Proms premiere.
Paul Vaughan talks to musicians and historians, and follows its trail as the words of Land of Hope and Glory were set to it for Edward VII's Coronation by a schoolmaster at Eton, and thanks to the formidable singer Dame Clara Butt it became the country's second national anthem during the First World War.
This year's Last Night of the Proms the tune will be roared out once again by the thousands in the Albert Hall and around the country.
Gosh, said Elgar, Ive got a tune in my head.
He wasn't wrong.