Career
He was sent with Melchior Borchgrevinck, Truid Aagesen, Wilhelm Egbertsen, and Mogens Pedersøn to study with Giovanni Gabrieli in Venice 1599–1600. A result of his studies was his Opus 1 madrigal collection of 1606, published under his Italianized name Giovanni Fonteio. This set of 21 madrigals was the first such collection by a Danish composer, two years before Pedersøn"son
He served as lutenist at the court of Christian IV as and after Pedersøn"s death in 1623 Nielsen was promoted to Deputy Kapellmeister, but left the court the following year.
T"amo, mia vita from – on Music from the time of Christian IV – Madrigals from the South to the North.