Ambrosian chant is a plainchant attributed to St. Ambrose. It is also called the Milanese chant because St Ambrose was the Bishop of Milan from 374 to 397. The Ambrosian chant was primarily associated with the Archdiocese of Milan and northern Italy until around the 8th Century. It is unlikely that St. Ambrose composed the melodies that make up the Ambrosian Chant, although it is not entirely clear who composed the melody. He is been recognized as composing for many hymns, both text and chants.
The most prominent four hymns, Aeterne rerum conditor, Deus creator omnium, Jam surgit hora tertia, and Veni redemptor gentium are still being used today in the Ambrosian Rite services. There were many impersonators at the time and it has made it difficult to pinpoint exactly which hymns St. Ambrose actually created himself.
Sometime between the 8th Century and the 13th Century the Gregorian chant became extremely popular. The styles of the Ambrosian Chants and the Gregorian Chants are very different.The Ambrosian Chant was intended to be sung by males and often specific stations of the church were required to sing the chants, such as the boy choir or the deacons.
The songs were sung in one monophonic tone by the chanters. The chants are an essential part of the Roman Catholic Churches celebrations and worships of the Ambrosian Rites.
The Ambrosian Chants serves two functions in the Ambrosian Rites. First it is used in Offices of the Church. The chants are the 150 Psalms that are sung at Matins and Vespers in rotation. All 150 Psalms are sung every two weeks.
These rites differ from the Gregorian rites in several ways. One of the most significant things you will notices is the manner of using the incense during the rite. Second, the Ambrosian Chants are used in Mass for affirming faith. Also they are sung to accompany spiritual lessons and there are different chants for different celebrations.
Ambrosian Chants are sung throughout the liturgy. The Ambrosian Rite is simply a series of songs, Psalms, prayers and actions that lead services and create a Mass. There are different chants to be sung for the Time of Lent, for First Sunday and more occasions.
The Twelve Kyrie is chanted before Solemn High Mass performed during solemn occasions. There is the Alleluia chant as well as Evangelium Antiphous to name a couple more.The rites are performed using these beautiful chants to praise and worship during services.
Ambrosian musical manuscripts can only be dated back to the 12th Century according to Albert Turco. The earliest manuscripts were divided by a winter book and a summer book. The Ambrosian Chants along with the Gregorian Chants have survived the years and are offically sanctioned by the Roman Catholic Church.
It is important to preserve this type of worship for several reasons. The two most important is because of the beauty and sheer age of the plainchant style of singing and its place in the historical formation of the Roman Catholic Churches worship. The ancient custom of having a different Preface for every Mass was preserved by the Ambrosian Chants.