LISTEN - Coronation Choir in Westminster Abbey Sings a Beautiful Gloria by Catholic Convert William Byrd during the Ceremony for King Charles III - VIDEO

The Coronation Choir sing William Byrd’s ‘Gloria in Excelsis Deo’ from the Mass for Four Voices during King Charles III’s coronation service. 
This was written by the famous English composer William Byrd. Byrd, who was born circa 1540 and died on the 4th of July 1623, was a Renaissance composer who converted to Catholicism during the persecution in England. (Full Lyrics below the Video)
The Mass for Four Voices is a choral Mass setting, written around 1592–1593 during the reign of Queen Elizabeth I, and is one of three settings of the Mass Ordinary which he published in London in the early 1590s.
"Gloria in excelsis Deo" (Latin for "Glory to God in the highest"), also as the Greater Doxology (as distinguished from the "Minor Doxology" or Gloria Patri), and the Angelic Hymn or Hymn of the Angels. The name is often abbreviated to Gloria in Excelsis or simply Gloria.  The hymn begins with the words that the angels sang when announcing the birth of Christ to shepherds in Luke 2:14 (in Latin). Other verses were added very early in history.
Lyrics in Latin with English Translation below:

Glória in excélsis Deo et in terra pax homínibus bonæ voluntátis.
Laudámus te, benedícimus te, adorámus te, glorificámus te,
grátias ágimus tibi propter magnam glóriam tuam,
Dómine Deus, Rex cæléstis, Deus Pater omnípotens.
Dómine Fili Unigénite, Iesu Christe, Dómine Deus, Agnus Dei, Fílius Patris, qui tollis peccáta mundi, miserére nobis;
qui tollis peccáta mundi, súscipe deprecatiónem nostram.
Qui sedes ad déxteram Patris, miserére nobis.
Quóniam tu solus Sanctus, tu solus Dóminus, tu solus Altíssimus,
Iesu Christe, cum Sancto Spíritu: in glória Dei Patris. Amen. 

English : Glory to God in the highest,
and on earth peace to people of good will.
We praise you, we bless you, we adore you, we glorify you,
we give you thanks for your great glory, Lord God, heavenly King,
O God almighty Father. Lord Jesus Christ, Only Begotten Son,
Lord God, Lamb of God, Son of The Father,
you take away the sins of the world, have mercy on us;
you take away the sins of the world, receive our prayer;
you are seated at the right hand of the Father, have mercy on us.
For you alone are the Holy One, you alone are the Lord,
you alone are the Most High, Jesus Christ, with the Holy Spirit,
in the glory of God the Father. Amen.

Liturgical use: This is sung on high feast days and Sundays during the liturgical year except during Lent and Advent.