Kuhlau, Frederik Danish composer and pianist of German birth. After studying in Hamburg he established himself in Copenhagen as a pianist and composer, gaining success with his Piano Concerto op. 7 and his Singspiel Røverborgen (1814). He was well received in Stockholm and in Vienna he met Beethoven, whose works he championed. Though best known for his Classical piano works and fashionable flute music, he also wrote fine chamber music including the Quintet op. 51 and the Flute Sonata op. 69, the opera Lulu (1824) and the popular incidental music (incorporating folktunes and the national hymn) to Heiberg's frequently performed play Elverhøj (1828). His piano sonatas are popular teaching pieces and his sonatinas for piano duet have become classics. With C. E. F. Weyse Kuhlau was the foremost composer of the late Classical and early Romantic periods in Denmark.