Gregorian chant is also known as plainchant or plainsong, and is a form of monophonic, unaccompanied singing, which was developed in the Catholic church, mainly during the period 800-1000. It takes its name from Pope St. Gregory the Great.
This music was traditionally sung by monks or other male clerics, and was used during religious services. It is the music of the Roman Rite of the Mass, also known as the Gregorian rite or Tridentine rite. Other rites of the mass, such as the Assyrian or Coptic use different melodies but share the unaccompanied and monophonic nature of the Gregorian, which allude to a common source.
Unaccompanied singing has entered the Liturgy of the Christian church since its beginnings, and was probably inherited from Jewish customs in temple and, later, synagogue services. About the first few centuries, up until about 400, information is very scant indeed. The best we can get is information from the Old and New Testament and other ancient sources. Most of them write in a very poetic or obscure way about music, so its hard to make any sound statements about how music sounded in these first centuries.
In the next few centuries, information is still rare, so scholars are still hotly debating the period between roughly 400 and 800. It appears that in the latter part of the seventh century, a large part of the Roman Mass had been put together rather consciously in a short period of time. The music to accompany the Mass was apparently also collected in this period. Since Gregorian chant is remarkably uniform in geographically very distant regions, and this unification happened in a rather short time, most likely around 800, the bulk of evidence suggests that a major effort at making the repertory consistent happened at this time. In addition, the stylistic unity of the chant suggests that a large amount of the actual music was composed around the same time and place. Most likely--though extremely difficult to prove--much of the actual chant composition, as we know it today, took place in the Frankish domain during the Carolingian Renaissance, under the combined guidance of Charlemagne and the popes.
Detailed recent study also shows numerous survivals of earlier reportories of chant. Sometimes there are actual repertories that are still sung in a specific place (a good example is Ambrosian Chant , which originated in Milan, and was preserved due to the reputation and authority of St. Ambrose who is reputed to have written many of its earliest hymns); or repertories that survived because they were in isolated locations shielded from the edicts of Rome, which was attempting to establish a consistent practice during this period (an example is the Mozarabic Rite, which survived in Spain from the time of the Visigoths, through the domination by the Moors, until about the 12th century); and in other cases older chants were incorporated into the actual Gregorian chant, and can be pieced together by careful stylistic dissection of the originals. In all likelihood, chant is at least as old as the breakup of the western Roman Empire in the 5th century, but mutated into different forms in different regions until brought together into one unified repertory under Charlemagne.
In the ninth and tenth century, the first sources with decipherable musical notation are found. Most scholars of Gregorian chant agree that the development of music notation assisted the dissemination of chant across a thousand miles of Europe; indeed it may have been impossible any other way, since there is no evidence of mutation across distance. Survivals of notated manuscripts, however, are few, and restricted to a few locations in Germany (Regensburg), Switzerland (St. Gall) and France (Laon, St. Martial ). Most of the Gregorian chant familiar today, at least that in the Mass, has changed little since this time.
The music and its performers
Many hear Gregorian chant and think of it as a very simplified version of modern music (partially due to the fact that it is usually accompanied surprisingly fittingly by an organ playing chord progressions popular in modern music along with the chanted melody). While it is simple in its lack of harmony, the modal system involved is quite complex, and is directly descended from the system used by the ancient Greeks.
The Gregorian system is based upon the same scale used in modern music, an 8 note scale: Do-Re-Mi-Fa-Sol-La-Ti-Do.
In most Western music since the Renaissance there are two modes: Major and minor. The Major scale is built upon the Do and the minor scale the La. The various keys that are used affect only the range of the notes, or the pitch. Essentially the scale is the same, only transposed, or moved, to a different range.
The Gregorian system uses the theoretical system of 8 modes. While some pieces fall outside these modes, most obey the theory. The actual theory behind modality is quite complicated, but essentially each mode is a unique scale system, in addition to our Major and minor scales. Chant allows only one accidental on Ti (equivalent to Bb, but the actual pitch is variable) which adds complication to the 8 modes. In this manner Plainsong is much richer than the simplified bimodal modern system, but this makes some of the sounds of Gregorian Chant unusual and even somewhat uncomfortable to ears attuned to modern scalar modes.
Unlike modern music there is no beat or regular accent to Gregorian Chant. In fact the time is free, allowing the accenting of the text, which often includes sections of unequal length and importance.
The actual pitch of the Gregorian chant is not fixed, so the piece can be sung at any range, so long as the intervals are respected.
Chant is commonly written on a staff similar to the modern 5-line-4-space staff, but the Gregorian staff has 4 lines and 3 spaces. The notes, called neumes, are somewhat similar to modern notes, but often do not include stems and can be stacked, not to create harmonic chords, but to indicate the sequence.
Traditionally chant would be sung only by men, as it was originally simply the music sung by all the clergy (all male) during the Mass and Office (prayer sessions scheduled 7 times throughout the day). As the Church expanded away from the larger cities, the number of clergy at each Church dropped and lay men started singing these parts. In Convents women were permitted to sing the Mass and Office as a function of their consecrated life, but the choir was still considered an official liturgical duty reserved to clergy, so lay women were not allowed to sing in the Gregorian Schola or chant choir.
As harmony began to develop in the middle ages and into the Renaissance younger boys and castrati would sing the high parts. As these numbers dwindled and the music became popular away from the major cities women gradually were permitted to sing the polyphonic parts.
Eventually Popes, especially Pope St. Pius X encouraged the faithful to sing the Ordinary of the Mass. Restrictions were still made for the Propers of the Mass, which are for the Tridentine Mass still customarily reserved to the clergy and lay men with the notable exception of Convents.
Gregorian chant in the liturgy
Gregorian chant, like the chants of the other rites, was later used to sing only certain parts of the liturgy. The rest of the parts are sung by the bishops, priests, and deacons with a certain default assigning of notes to words depending on their place in a sentence. The parts sung in the Gregorian chant style in the Roman Mass include:
- The Kyrie
- The Introit
- The Gloria
- The Graduale
- The Credo
- The Offertory
- The Sanctus and Benedictus
- The Agnus Dei
- The Communion
The Introit, Graduale, Offertory and Communion texts are called the Propers because they are "proper" to day and season. The Kyrie, Gloria, Credo, Sanctus, Benedictus and Agnus Dei remain unchanged, being "ordinary" parts of the Mass and thus called the Ordinary of the Mass.
It should be noted that the Catholic church allowed later music written by individual composers, such as Giovanni Pierluigi da Palestrina, to replace the Gregorian chant the Ordinary of the Mass. This is why for example a Mozart Mass would feature the Kyrie but not the Introit.
The Propers may be replaced by choral settings, as well, on certain solemn occasions. Among the most frequent to compose such polyphonic replacements for the Gregorian chant Propers was English composer William Byrd.
Even with the advent of harmonic melody Gregorian Chant is the official music of the Catholic Church and Popes have enjoined the faithful to give chant the pre-eminence it deserves.
- Willi Apel, Gregorian Chant. Bloomington etc.: Indiana University Press, 1973. Fine, digestible first introduction, with an emphasis on musical analysis.
- David Hiley, Western Plainchant. Oxford: Oxford University Press, 1993. Excellent encyclopedic work, good for quick reference and thorough first introduction, much broader in scope than Apel's book, but also at times less in-depth. With the largest bibliography I have ever seen...
- Peter Wagner, Einführung in die Gregorianischen Melodien. Ein Handbuch der Choralwissenschaft. Three thick parts. Leipzig: Breitkopf & Härtel, 1911. After more than hundred years, still the classic study. Obviously dated here & there.