Ambrosian chant

Ambrosian chant (also known as Milanese chant) is the liturgical plainchant repertory of the Ambrosian rite of the Roman Catholic Church, related to but distinct from Gregorian chant. It is primarily associated with the Archdiocese of Milan, and named after St. Ambrose much as Gregorian chant is named after Gregory the Great. It is the only surviving plainchant tradition besides the Gregorian to maintain the official sanction of the Roman Catholic Church.

The history of Milan as a center for religious music goes back to St. Ambrose. Ambrose is not known to have composed any of the Ambrosian chant repertory, much as Gregory the Great is not known to have composed any Gregorian chant. However, during his fourth-century tenure as Bishop of Milan, he is credited with introducing hymnody from the Eastern Church into the West. Ambrose composed original hymns as well, four of which still survive, along with music which may not have changed too much from the original melodies.

Two methods of singing psalms or other chants are responsorial and antiphonal. In responsorial singing, the soloist (or choir) sings a series of verses, each one followed by a response from the choir (or congregation). In antiphonal singing, the verses are sung alternately by soloist and choir, or by choir and congregation. In the Western Church where formerly the responsorial method seems to have been used alone, the antiphonal method was introduced by St. Ambrose.

Over time, the Milanese liturgy developed into the Ambrosian rite, which shares more in common with the Gallican and Mozarabic rites than with the Roman. Ambrosian chant developed to meet the particular needs of the Ambrosian liturgy. Although the Ambrosian rite is liturgically related to other rites and Ambrosian chant is musically related to other plainchant traditions, different categories of chant, different chant texts, and different musical styles make Ambrosian chant a distinct musical repertory. By the 8th century, this chant was attested to be normative across northern Italy, perhaps reaching into southern Italy as well.

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