Giovanni Gabrieli (c. 1554/1557 – 12 August 1612) was an Italian composer and organist. He was one of the most influential musicians of his time, and represents the culmination of the style of the Venetian School, at the time of the shift from Renaissance to Baroque idioms.
Gabrieli was born in Venice. He was one of five children, and his father came from the region of Carnia and went to Venice shortly before Giovanni's birth. While not much is known about Giovanni's early life, he probably studied with his uncle, the composer Andrea Gabrieli; he may indeed have been brought up by him, as is implied by the dedication to his 1587 book of concerti, in which he described himself as "little less than a son" to his uncle. He also went to Munich to study with the renowned Orlando de Lassus at the court of Duke Albert V; most likely he stayed there until about 1579. Lassus was to be one of the principal influences on the development of his musical style.
By 1584 he had returned to Venice, where he became principal organist at Saint Mark's Basilica in 1585, after Claudio Merulo left the post; following his uncle's death the following year he took the post of principal composer as well. Also after his uncle's death he began editing much of the older man's music, which would otherwise have been lost; Andrea evidently had had little inclination to publish his own music, but Giovanni's opinion of it was sufficiently high that he devoted much of his own time to compiling and editing it for publication.