Because Elgar is right for all occasions.
How an Elgar march became 'Land of Hope and Glory' at the suggestion of the King.
As preparations got under way in 1901 for the coronation of King Edward VII, the Covent Garden Grand Opera Syndicate commissioned Elgar to write a work to be premiered at a Royal gala on the eve of the Coronation which was scheduled for July 1902.
The King himself suggested to Elgar that words could be provided to the Trio section of the first Pomp and Circumstance March, which His Majesty liked. Elgar took up the King's suggestion and asked the writer A.C. Benson to provide words so that the tune could form the climax of the Ode.
When they saw the section which featured the Trio – now with Benson’s added lyrics ‘Land of Hope and Glory’ – Elgar’s publishers asked him to revise it so it could be produced as a separate song. This was in fact sung by Clara Butt with great success at a "Coronation Concert" a week before the Ode was first performed in London.
In the event the Coronation was postponed owing to the King being ill, so the first performance of Coronation Ode was not until 2 October 1902 at the Sheffield Festival.