The Ambrosian, or Milanese, liturgy shared common features with both Western and Eastern rites and served as a link between them. A central feature of the Ambrosian liturgy is its Christocentric nature, reflecting an ongoing struggle with Arian influence. Never suppressed by ecclesiastical authorities, the Ambrosian liturgy continues in use today.
Though usually associated with the metropolitan see once occupied by Saint Ambrose (d. 397), the Ambrosian rite includes in addition to the liturgy celebrated in the city of Milan (i.e., the Milanese liturgy), the liturgy of several other dioceses of Northern Italy (Bergamo, Ticino, Novara, Vercelli, etc.), and to a certain extent, the liturgy of Aquileia.
Unlike the other non-Roman Western rites, the Ambrosian liturgy was never officially suppressed by the emperor or pope. In spite of Carolingian and later attempts to “Romanize” everywhere, the Ambrosian liturgy survived with numerous medieval accretions (Roman and non-Roman), but underwent major restorations first under Carlo Borromeo (d. 1584) and then at the beginning of the twentieth century under Cardinals A. Ratti (later Pius XI) and I. Schuster. It was completely revised and translated into Italian in the 1970s.
The liturgical patrimony of the Ambrosian liturgy was largely the result of strong Roman and Eastern influences. After its emergence as a distinct rite, it came to share many of its features with all the Western rites, often serving as the bridge between East and West. What distinguishes it from all the other liturgical traditions, however, can be understood only in the context of the theological and political anti-Arianism in which it arose and evolved. With the exception of the Roman liturgy, the Arian controversy had a major effect on the euchology of all the Western traditions, though in no case did this struggle perdure as at Milan. In fact in its emergence (fourth-fifth centuries), its development (sixth–seventh centuries), and in the period of its stabilization (eighth–ninth centuries) the Ambrosian liturgy had to fight constantly against this heresy in one form or another. The most obvious result is the strong Christocentricism of the Ambrosian prayers, in both original texts and in the editing of texts borrowed from Roman and Carolingian sources.
The centrality of Christ is manifest not only in the careful consideration of the Incarnation and the virginal birth but also in the veneration of the Virgin Mary. In Ambrosian iconography, it is possible to trace a progression from the Kyrios-Pantocrator to Deus-Homo, Homo-Deus, and Nobiscum-Deus, which corresponds to the various stages in the development of Ambrosian euchology. It is here that the Ambrosian influence on the other Western liturgies was most strongly felt.
In the early Middle Ages, the Ambrosian Eucharist had the following order:
INGRESSA
Kyrie
Oration super populum—collect
PROPHETIC LESSON
Psalmellus
EPISTLE
Alleluia with verse (Cantus during Lent)
GOSPEL
Homily
Dismissal of Catechumens
Kyrie and Antiphona post Evangelium
Pax
Oratio super sindonem
Offertory procession: ̧Offerenda with verses
Proper Preface and Sanctus
Invariable Canon
Fraction and Commixtio; ̧Confractorium
Lord’s Prayer and embolism
COMMUNION
̧Transitorium no psalm
Oratio post communionem
Kyrie and Dismissal
The Ambrosian office was unique in the West in spreading the psalter over two weeks. Like the Roman and Benedictine cursus, however, the Ambrosian assigned Psalms 109/110–147 to vespers. As in the cathedral office of fourth-century Jerusalem and the “Chaldean” rite, the morning office at Milan consisted of three canticles, the Laudate psalms (148–150), gospel reading, and a procession to the cross or baptistry, while vespers began with the lucernarium.
The Ambrosian chant tradition is preserved in some 300 north Italian manuscripts, most from the late twelfth century and later. Though sharing many features and texts with the Gregorian chant, the Ambrosian has a closer affinity to the Old Roman and Beneventan traditions.