William Mundy (c. 1529–1591) was a Renaissance English composer of sacred music and father of composer John Mundy. Over four hundred years after his death, William Mundy's music is still performed and recorded.
Mundy was the son of Thomas Mundy, a musician and sexton of the London church St Mary-at-Hill. William Mundy married Mary Alcock and had two sons, John Mundy, an organist and composer, and Stephen Mundy, a gentleman of the household to James I and Charles I.
In 1543, William Mundy was head chorister of Westminster Abbey, until his voice broke at puberty. He was appointed deputy to St Martin, Ludgate in 1547, and from 1548 to 1558 Mundy served as Parish Clerk for the church of St Mary-at-Hill in London (his father Thomas' employer). Mundy was appointed Vicar choral to the Chapel Royal in 1559, and as a Gentleman of the Chapel in 1564, and remained in that position for twenty-seven years until his death around early October 1591.
Coming of age during the reign of Henry VIII, Mundy's career spanned much of England's Tudor Dynasty, and reflected the changes in church music that accompanied the religious turmoil of that period. Mundy's earliest surviving works, a Magnificat, Mass Apon the Square I, Mass Apon the Square 2, a Alleluia Post partum, a Alleluia Per te Dei, and a Kyrie, possibly date from the 1550s, and appear in the Gyffard Partbooks. Mundy's extant body of sacred music consists of the two masses above, six Anglican service settings, the single Kyrie, twenty-two motets (in Latin), thirteen anthems, and large number of musical settings for specific Psalms. These settings included his versions of Miserere mei Deus (from Psalms 51), Adolescentulus sum ego (from Psalms 119), In aeternum (also from Psalms 119), and Let the sea make a noise (from Psalms 98), which was composed for twelve instruments. Towards the end of his career, Mundy remained innovative as English sacred music continued to transform during the Elizabethan era. He was a pioneer of the genre of verse anthem with organ accompaniment (along with Richard Farrant and William Byrd) in works such as Ah, helpless wretch and The secret sins.