Jacobus Gallus Carniolus (a.k.a. Jacob(us) Handl, Jacob(us) Händl, Jacob(us) Gallus; Slovene: Jakob Petelin Kranjski) (3 July 1550 – 18 July 1591) was a late-Renaissance composer of Slovene ethnicity. Born in Carniola, which at the time was one of the Habsburg lands in the Holy Roman Empire, he lived and worked in Moravia and Bohemia during the last decade of his life.
Gallus may have been named Jakob Petelin at birth.Petelin means "rooster"; handl and gallus mean the same in German and Latin, respectively. He was probably born in Reifnitz (now Ribnica, southern Slovenia), although Slovene folk tradition also claims his birthplace to be at Šentviška Gora in the Slovenian Littoral. He used the Latin form of his name, to which he often added the adjective Carniolus, thus giving credit to his homeland Carniola.
Gallus most likely was educated at the Cistercian Stična Monastery in Carniola. He left Carniola sometime between 1564 and 1566, traveling first to Austria, and later to Bohemia, Moravia and Silesia. For some time he lived at the Benedictine Melk Abbey in Lower Austria. He was a member of the Viennese court chapel in 1574, and was choirmaster (Kapellmeister) to the bishop of Olomouc between 1579 (or 1580) and 1585. From 1585 to his death he worked in Prague as organist to the Church of St. John on the Balustrade (Czech: Sv. Jan na Zábradlí). Gallus died on 18 July 1591 in Prague.