The Piano Sonata No. 14 in C-sharp minor “Quasi una fantasia”, Op. 27, No. 2, by Ludwig van Beethoven, popularly known as the Moonlight Sonata (Mondscheinsonate in German), was completed in 1801. It is rumored to be dedicated to his pupil, 17-year-old Countess Giulietta Guicciardi, with whom Beethoven was, or had been, in love. The name “Moonlight” Sonata derives from an 1832 description of the first movement by music critic Ludwig Rellstab, who compared it to moonlight shining upon Lake Lucerne.