A Dictionary of Music and Musicians/Gloria
GLORIA is the name which is generally applied in England to the short hymn Gloria Patri, and in the Roman Church to the longer hymn Gloria in Excelsis, which is also called the 'Great Doxology,' or 'Angelical Hymn,' because its first words are those of the angels who appeared to the shepherds. The former is of unknown origin, and was in use in the Anglo-Saxon offices. The custom of singing it after each psalm is peculiar to the Western Church.
The Gloria in Excelsis is probably of Eastern origin. In the Western Church it was formerly used at the beginning of the Liturgy when the Te Deum was used at the end. In the Mass it follows the Kyrie. It now comes at the conclusion of the Communion Service in the English Church, immediately before the blessing. It appears in the Common Prayer Noted of 1550 with an adaptation of the old church melodies by Marbeck, but it does not appear to have been sung in the early days after the Reformation in England, and received little attention from English composers. At the present day it is set equally with the other portions of the Communion Service.[ C. H. H. P. ]