ISAAK (IZAC), HEINRICH - Catholic Encyclopedia, Vol. VII, p. 155

Machine translation of the 1948–1954 Italian original. The original text is authoritative.

ISAAK (IZAC), HEINRICH. - Flemish composer, b. ca. 1450, d. at Florence in 1517. He first lived at the court of Ferrara, then became organist and chapel master at S. Giovanni and at the court of Lorenzo il Magnifico in Florence (1480–92), where he was called Enrico il Tedesco.

He is found for some years at Innsbruck, again at Florence, then at Augsburg, and from 1497 at the court of Massimiliano in Vienna. In 1514 he returned to Florence. Ten masses were printed at Venice in 1506 under the title Missae Henrici Izac; another collection of 13 masses appeared there in 1539.

Article illustration — Motets, psalms and hymns in collections by Petrejo (ibid. 1539) and Rhaw (Nuremberg 1541); many other compositions in collections of the period and later. The music of I., in a highly developed contrapuntal and polyphonic style, enjoyed wide circulation in its time.
(from G. burbagallo, *Storia Universale*, IV, part 18, Turin 1911, p. 21) ISABELLA LA CATTOLICA - Portrait, from a print in the Bibliothèque nationale of Paris.

BIBL.: P. Wagner,
Geschichte der Messe,
Ratisbona 1914, pp.
282-317; H. Rietsch,
H. I. und das Innu-
bruchlied, in Jahrbuch
Peters, Lipsia 1917; M.
Bakolzer, Studies in me-
dioeval and renaissance
music, Nuova York
1930, pp. 191 and 196.
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