Composer, Author, Singer, Diplomat. He is principally known for his important books on the German Baroque era, though his music has recently enjoyed a resurgence of interest. Mattheson was born in Hamburg and was based there until his death. A well-regarded tenor, he sang over 60 roles with the city's opera company after 1696, including the leads in several of his own operas. He formed a close friendship with George Frideric Handel, then a violinist in the opera orchestra, and at his suggestion they competed for Buxtehude's post as music director of Lubeck. They discreetly withdrew after learning that marrying the boss's daughter was a requirement for the job. The most famous episode of Mattheson's life also involved Handel. Both were hot-tempered, jealous types, and a quarrel during a performance of "Cleopatra" (1704) resulted in a duel; Mattheson would have killed the future author of "Messiah" had his sword not split against one of his opponent's tunic buttons. Amazingly, they were soon reconciled and Handel even wrote two important tenor roles for him to sing. From 1706 he was chiefly employed as a secretary to the Wich family, England's Ambassadors to Hamburg. He spoke English fluently, made many diplomatic missions to London, and married an Englishwoman in 1709. Music was not ignored: Mattheson became Kapellmeister of Hamburg Cathedral in 1715 and to the Duke of Holstein four years later, and he continued to compose long after deafness forced him to resign his posts in 1728. His literary writings cover the full spectrum of German musical practice of his day. Of particular note are the "Critica Musica" (1722 to 1725), the first German musical periodical, which he edited and wrote almost single-handed; and the "Grundlage einer Ehren-Pforte" (1740), a biographical lexicon of 149 German musicians. (J.S. Bach is conspicuously missing from the latter because he refused to supply Mattheson with personal information). He also translated the novels of Samuel Richardson into German. Mattheson's surviving music includes eight operas, 26 oratorios and Passions, and some chamber works. The manuscripts were thought to have been lost in the destruction of the Hamburg State Library at the end of World War II, but they resurfaced in Armenia in the late 1990s and have since been returned to Hamburg. His opera "Boris Goedonov" (1710) - predating Mussorgsky's classic by 160 years - was successfully staged in 2005.