The Gallican Rite is a historical version of Christian liturgy and other ritual practices in Western Christianity. It is not a single rite but a family of rites within the Latin Church, which comprised the majority use of most of Western Christianity for the greater part of the 1st millennium AD. The rites first developed in the early centuries as the Syriac-Greek rites of Jerusalem and Antioch and were first translated into Latin in various parts of the Western Roman Empire Praetorian prefecture of Gaul. By the 5th century, it was well established in the Roman civil diocese of Gaul, an early center of Christianity. Ireland too is known to have had a form of this Gallican Liturgy mixed with Celtic customs. The rites can be considered part of what is now the Western branch of the Catholic Church.
The Gallican Rite was used from before the 5th century, in what known was prior to the Diocletian reform in AD 293 Roman Gaul, until the middle or end of the 8th century. There is no information before the 5th century and very little then; and throughout the whole period there was, to judge by existing documents and descriptions, so much diversity that, though the general outlines of the rite were of the same pattern, the name must not be taken to imply more than a very moderate amount of homogeneity. The Rite of Iberia, used from the 5th century, in Roman provinces within the Roman civil diocese of Hispania, to the end of the 11th century, and lingered as an archaeological survival in chapels at Toledo and Salamanca, was so nearly allied to the Gallican Rite that the term Hispano-Gallican is often applied to the two. But the Iberian Mozarabic Rite has, like the allied Celtic Rite, enough of an independent history to require separate treatment, so that though it will be necessary to allude to both by way of illustration, this article will be devoted primarily to the rite once used in what is now France. Of the origin of the Gallican Rite there are three principal theories, between two of which the controversy is not yet settled. These theories may be termed: the Ephesine, the Ambrosian, and the Roman.