About
(b. Flanders, c. 1450; d. Florence, 26 March 1517).
Flemish composer. Though he was born in Flanders, no references to him there are known; the earliest (1484) concerns an apparent journey south, through Innsbruck, to Italy. Serving the Medici in Florence, 1485-93, he sang at the cathedral and probably taught Lorenzo the Magnificent's children. From 1496 he worked intermittently in Vienna, Torgau, Konstanz and Florence, notably as court composer to the Habsburg Emperor Maximilian I. From 1514 he remained in Florence, holding both a Medici pension and a diplomatic post under Maximilian.
Isaac's works reflect his knowledge of the distinctions among Netherlands, Italian and German musical practices; he adapted well to local tradition wherever he found himself. Half his nearly 40 settings of the Mass Ordinary, for example, use "foreign" borrowed material (e.g. secular songs) and imaginative cyclic structures in accordance with Netherlands-Italian practice, while the other half (dating from after 1496) use plainchant and more conservative, self-contained structures, often with unison sections. The German style is found above all in his nearly 100 settings of the Proper, especially in the posthumous three-volume collection Choralis constantinus, written for the Habsburg court chapel and for Konstanz. His secular works include imitative chansons and homophonic frottolas as well as German Tenorlieder (Isbruck, ich muss dich lassen is famous for the lyricism of its polyphony). In quality and scope Isaac's works stand beside those of Obrecht, Compere, Agricola and La Rue as some of the finest of the Josquin period; his influence, through his music and his pupil Senfl, was particularly important in Germany.
- MUZE