Franco-Flemish composer. From an early age he lived in Italy, at first as choirboy in Naples and Novellara near Modena), and then as a pupil of Rore at Ferrara (c.1550-5). He directed music at the court of Novellara before 1558, and then served the Duke of Mantua and (in 1561) the Duke of Parma. In 1563 he was in Milan, directing music for the Spanish governor, but he returned to Mantua in 1565 to be choirmaster at the ducal chapel of S. Barbara where he stayed till 1583 when he was succeeded by Gastoldi. His personal relationships were stormy, his wife deserted him, and he had an ill-fated love affair with a singer at the Ferrara court.
Wert was one of the leading 'virtuoso' madrigalists of the late sixteenth century, and the last of the great Flemings who settled in Italy. He published thirteen volumes of madrigals (mostly à 5), one of canzonette, two of motets and one of hymns, and much more appeared in anthologies. He stands as the link between Rore and Monteverdi, whose early madrigals show his influence very strongly. Wert developed a fastidious attention to declaiming the texts he set, using a kind of choral recitation; he often favored brilliant virtuoso scoring with the three upper voices emphasised--in recognition of the talented court singers for whom he was writing; and his vocal lines are highly individual and dramatically angular in certain 'mannerist' works. He was a friend of the poet Tasso, whose verses he liked to set.