Guilielmus Messaus

Guilielmus Messaus (or Messaulx, Missau) (bapt. 2 July 1589 – 8 March 1640) was a Flemish composer who was born and died in Antwerp.

Between 1609 and 1610 he was a sacristan of St. Joris and in 1613 he became a schoolmaster and sacristan at St. Wllibrordus. From 1614 to 1618 he was also a teacher at St Walburgis and St Andries, but was dismissed for bad behaviour. From before 1620 he was a singer and a choir-master at St Walburgis, a post he held until his death. We know this because in 1620 he was temporarily suspended due to refusing to perform a plainchant mass instead of a polyphonic one for the burial of a child.

Messaus composed at least 14 masses, 57 motets, Dutch hymns, a canon and 3 secular songs in Dutch. He is now remembered mostly as a very productive musical arranger of cantiones natalitiae (Christmas songs), which were very popular in the Low Countries. He was also an active copyist of motets and harpsichord music.