clemens erwein heinrich karl bonaventura freiherr von und zu franckenstein (14 july 1875 – 19 august 1942) was a german opera composer, studying in vienna, austria, and later in munich, germany, with ludwig thuille and at the hoch conservatory in frankfurt with iwan knorr. after a visit to the usa he conducted the moody-manners opera company in england from 1902–1907, then worked at the court theatres of wiesbaden and berlin, until the court theaters were abolished after the first world war. he was general director of the bayerische staatsoper in munich (1912–1918 and 1924–1934). he produced the munich opera festival through 1934 when he was forced out by nazi prohibitions.