Who composed the Enigma Variations?

Elgar, in 1899, and the enigma is a puzzle he set deliberately and never solved for anyone. Each variation is a musical portrait of a friend, identified only by initials or a nickname, and Elgar said that in addition there was a larger theme running through the whole work which is never played - a tune that fits the piece but is not in it.

People have been guessing for over a century. Auld Lang Syne, Rule Britannia, Pop Goes the Weasel, Ein feste Burg, and Pergolesi have all been proposed, along with the argument that the hidden theme is not a tune at all but friendship, or silence itself. Elgar took the answer to his grave and enjoyed the speculation, remarking that its dark saying must be left unguessed.

The famous variation, Nimrod, is a portrait of his publisher's assistant August Jaeger - Jäger being German for hunter, and Nimrod the mighty hunter in Genesis, so the title is a bilingual pun on a friend's surname. It commemorates an evening when Jaeger talked Elgar out of giving up composing entirely, and it is now played at British state funerals and remembrance ceremonies, which is a considerable afterlife for a joke about a colleague's name.