Many music lovers consider Beethoven to be the greatest musical genius who ever lived. The literature about him is expansive, since scholars continue to examine every aspect of his life and works. The general public has been no less curious, flocking to films such as Bernard Rose's Immortal Beloved (1994). Consequently, we know more about Beethoven than other composers‹or think we do. Even seasoned concertgoers, however, may be surprised at some unusual information about his background, life, and colorful personality. Consider the following:

• Beethoven's grandfather, also named Ludwig [Louis] van Beethoven (1712-1773), was the first of three generations of Beethoven musicians. Born in Antwerp, he later moved to Bonn to take the position of Hofkapellmeister in the court of Elector Maximilian Friedrich of Cologne.


• Under the tutelage of his most important instructor, Christian Gottlob Neefe, Beethoven learned Bach's complete Well-Tempered Clavier, 48 preludes and fugues that were not well known in the 1780s. He was playing them by memory in his early teens.


• Beethoven's first professional position was as court organist to Elector Max Franz in 1784. Five years later, he was playing viola in the elector's court orchestra; he was also a capable violinist.


• Jerome Bonaparte, Napoleon's youngest brother and king of Westphalia at the height of Napoleon's empire, offered Beethoven the position of Kapellmeister in 1808. (The composer declined.)


• After a visit to Vienna in 1817, the English piano maker Thomas Broadwood sent Beethoven a six-octave grand piano. According to Broadwood's biographer David Wainwright, "The case was Spanish mahogany, inlaid with marquetry and ormolu, the brass carrying-handles formed as laurel wreaths." Beethoven's name was inscribed along with a Latin translation noting the gift. Broadwood enlisted five other musicians to autograph the instrument, including the pianists Frederic Kalkbrenner and Johann Baptist Cramer. Franz Liszt acquired the instrument around 1846. Eventually he presented it to the Hungarian National Museum in Budapest.


• Twelve museums in five European countries are devoted to Beethoven. Four of them are in Vienna, where he lived for most of his life, moving frequently within the city.


• Beethoven's favorite composers were Mozart, Haydn, Bach, and Handel (he preferred Handel to Bach). Among older composers, he also revered Palestrina. Although he was critical of most contemporaries, he admired the operas of Spontini and Cherubini.


• The concept of heroism, and specifically the death of a hero, is a recurrent theme in such great Beethoven works as the "Eroica" Symphony, the oratorio Christ on the Mount of Olives, Op. 85, and the incidental music to Goethe's Egmont. But heroism surfaced much earlier in Beethoven's music. His first known composition was a funeral cantata from 1781 that has not survived; in 1790 the city of Bonn commissioned him to write the Cantata on the Death of the Emperor Joseph II. We know it as WoO 87.


• Most major composers have a thematic catalogue compiled by scholars. Bach has the Schmieder catalogue, abbreviated S. (or BWV for Bach Werke Verzeichnis); Mozart has the Köchel catalogue (source of the K. number); and Schubert the Deutsch catalogue (abbreviated D). Beethoven has multiple catalogues. Four 19th-century efforts were superseded by Georg Kinsky and Hans Halm's Das Werk Beethovens: Thematisch-Bibliographisches Verzeichnis in 1955, which is the standard. Kinsky and Halm included a special category, WoO, which stands for Werk ohne Opuszahl, or "work without opus number." Willy Hess published another catalogue in 1957 that catalogues Beethoven's unfinished works and sketches.


• Dozens of Beethoven's conversation books survive from 1818 until 1827. They reflect thoughts communicated to the deaf composer by his friends, family, and associates, but not his own comments since he usually responded verbally. Consequently, these books, while a valuable biographical source, require the reader to reconstruct Beethoven's half of the conversation. They are filled with details about everyday life, from gossip to family matters to medical maladies to weather. Comparatively few of the entries pertain to Beethoven's music.


• The familiar images of Beethoven show a craggy-faced man with wild, longish gray hair. All surviving portraits depict him as clean-shaven. During his last decade, however, he frequently allowed his beard to grow long, adding to his bizarre appearance. In these later years, most Viennese assumed that the famous composer, noted for his eccentricity, was more than a bit insane.


• In addition to deafness, Beethoven suffered from lifelong bouts of intestinal disorders, beginning in his teens. Modern physicians who have analyzed reports of his stomach complaints and contemporary diagnoses believe that he may have suffered from Crohn's disease, a chronic, recurrent inflammatory enteritis. His final illness was cirrhosis of the liver. At the time, his death was attributed to abdominal dropsy (the modern term is ascites, an accumulation of fluid in the peritoneal cavity of the abdomen). A recent theory put forward this past summer asserts that he may have been inadvertently poisoned by lead by his final physician, exacerbating his liver condition.