What was the name of Beethoven's famous piano piece for Elise?

Fur Elise, and nobody knows who Elise was. Beethoven wrote it in 1810 and never published it; the manuscript was found forty years after his death by Ludwig Nohl, who transcribed it and reported the dedication - and the original page has since been lost, so his reading cannot be checked.

The leading theory is that it says Therese rather than Elise, and that Nohl misread Beethoven's famously atrocious handwriting. Therese Malfatti was a pupil he proposed to in 1810 and who turned him down, and the manuscript was found among her papers. Other candidates have been proposed - a singer called Elisabeth Rockel, another Elise - and the argument is unresolved because the evidence was mislaid.

It is now among the most played pieces in the world and would probably have embarrassed him. It is a bagatelle, a trifle, of a kind he tossed off and did not think worth printing, and its fame rests entirely on being about the right difficulty for an intermediate student - which is a strange fate for a composer who spent his life trying to make the largest structures anyone had attempted.