At first, vestments were of one colour, white. Black was sometimes worn as a sign of mourning. A tenth or eleventh century writer speaks only of white vestments, except he refers to scarlet stripes (clavi) on the diaconal dalmatic, and says that black vestments were used during the procession on the feast of the Purification.
By the twelfth century, Rome had a canon regulating the use of colours for vestments. Pope Innocent III, who reigned from 1198 to 1216, is the first to mention four colours : white which the Roman Church used on feasts of confessors, virgins and on other joyful days; red used for martyrs, of the Holy Cross, and at Pentecost. Some, it seems also wore red for the feast of All Saints, but there is nothing strange in this as the feast was in origin the anniversary of the dedication, in AD 609, of the church of Our Lady, Queen of All Martyrs (the Pantheon in Rome). However, the Roman Curia wore white on this day. Black was used in penitential seasons and for Masses for the Dead ; green was used on common days because it was "midway between black and white". Pope Innocent regards violet as a variant of black and says the former was used on the feast of the Holy Innocents and Laetare Sunday. Scarlet and saffron yellow (coccineus et croceus) were considered as versions of red and green. Rose coloured vestments, he tells us, were sometimes worn for feasts of martyrs and yellow for confessors.
Until the introduction of chemical dyes in the nineteenth century, it was very difficult to produce a real black. Black was in reality a very dark shade of blue or green or brown. At the Catholic church in Croydon there is (or was some years ago) a set of "black" velvet vestments which date from the earlier years of the nineteenth century when vegetable dyes were still in use. When the priest stands at the altar wearing them the vestments look black, but laid out on the vestment press in the sacristy with the light shining on them from a different angle it is clear they are a very dark navy blue. When I was a boy, many of the old servers' cassocks (the cassocks were old, not the servers) in my parish church had faded very badly and patches of them were seen to be brown or green; they had been dyed with vegetable extracts.
The medieval Rites employed a greater number of colours and, because it was a matter of custom not rubric, there was considerable variation as to what colours were used for different feasts and seasons. Parish churches might have followed something of the colour scheme of the cathedral or some other great church, but much would depend in smaller churches on the number of sets (ore suits, as they are usually called in medieval records) of vestments which the local church owned.
The sacramentary of one great church in the Middle Ages listed as the vestments for use on ferias as "any old vestments the sacrist sets out" while elsewhere "the best vestments" irrespective of colour were specified for great feasts. The Bishop of Salisbury had vestments stitched with plates of gold, which tinkled as he moved. They must have very heavy to wear.
Amongst colours used then, but not in current use, were blue, yellow and unbleached linen. The last was the colour for Lent, sometimes "ash", a greyish colour was used for "Lenten array". In the Lyons Rite in France this was still the Lenten colour until the liturgical upheaval of the last three decades of the twentieth century, and, indeed may, for all I know, still be so in their New Order of Masses.
Blue and yellow were differently used in various places in, for example, the Sarum Use; blue was the colour for Virgins and Widows in some colour schemes with yellow for Confessors, in other places use of the two colours was reversed. Yellow continued until modern times as the colour for Confessors in the Carmelite Rite. That Rite also made use of blue as the colour for feasts of the Blessed Virgin Mary. These two colours are not used in the Roman Rite; although, exceptionally, blue was worn for feasts of Our Lady in the Roman Rite in Spain and, because it was converted from that country, in Spanish America. The usual explanation for this is that the Holy See granted an indult for the use of the colour as a reward to the Spanish for ridding Spain, and hence Europe, of the Mohammedans in 1492. This is, however, unlikely, as there were no compulsory liturgical colours at that time; it was purely a matter of custom.
In Florence in the Middle Ages, red and white striped vestments are known to have been worn on the feast of Corpus Christi : the colours of bread and wine.
In the Gallican Rites of France, red was the usual colour for the Blessed Sacrament. During the French Revolution, bishops and priests escaping from the Terror came to England. Some re-introduced the practice of burning a lamp before the Blessed Sacrament in the then newly established Catholic chapels, hence in many churches today the red sanctuary lamp is in the Eucharistic liturgical colour of the Gallican Rites, not that of the Roman Rite.
Until the introduction of the New Order (I have no idea of the present situation), the Pope wore only vestments of white, red and violet, using red, not black, for Good Friday and Requiem Masses.
It was not until the Missal of Pope St.Pius V, that there were rubrics requiring the uniform scheme of five colours for the Roman Rite.
White (albus) which is worn for the seasons of Christmas and Easter, on feasts of Our Lord and of Our Lady, on feasts of angels, the feast of All Saints and the feasts of saints who are not martyrs.
Red (ruber), which represents fire and blood, is worn on the feasts of the Precious Blood, the Holy Ghost, the Holy Cross, apostles and martyrs.
Green (viridis) vestments, the colour of hope, are used for the Sundays and Ferias after Epiphany and those after Pentecost.
Violet (violaceus) the colour of penitence, is worn in Advent and Lent, and on Rogation and Ember Days (except those of Pentecost when red is worn), the season of Septuagesima and Vigils (except those of the Ascension and Pentecost).
Black (niger), the colour of mourning, is used for Good Friday and for Requiems. Exceptionally, when Masses of the day are being celebrated (away from the High Altar) when the Blessed Sacrament is being exposed for the Forty Hours Devotion, on the Commemoration of All Souls (November 2nd), violet vestments are worn instead of black.
Rose colour (color rosaceus) vestments are prescribed by the Caerimoniale Episcoporum for use in cathedral churches and may be worn elsewhere instead of violet on the third Sunday of Advent (Gaudete) and mid-Lent Sunday (Laetare); on those two Sundays the Pope blessed golden roses for presentation to Catholic queens.
White may be replaced by real cloth of silver and white, red and green, but not violet or black, by real cloth of gold.
The Missal of 1962 (the reforms actually date from 1961) modifies the use of some of the colours prescribed by the Missal of Pope St.Pius V. The Pian Missal specifies violet vestments for the feast of the Holy Innocents (28th December), except when it falls on a Sunday when red replaces violet. The reform changed this to red on the feast on whatever day it fell, even though Pope Innocent III had recorded violet as being their colour even in his day. Red has been worn on the Octave day of the Holy Innocents, but the Octave was abolished in 1961.
Another variation which was "tidied up" was the replacement of violet vestments for the procession of candles on the feast of the Purification (2nd February) with white ones to match those of the Mass which follows. The procession seems, in fact, to be older than the Mass and, until 1961, followed the normal rule of violet vestments for processions of supplication.
The Holy Week reforms of 1956 which (with slight modifications) were incorporated into the 1962 Missal, also changed some of the traditional liturgical colours eg: the colour for the Palm Sunday procession was changed from violet to red and black for the Communion Rite on Good Friday was changed to violet.
As Abbot Cabrol wrote, "colours…have their own symbolism and speak to the eye: black tells of grief and mourning; violet is a sign of penance, red reminds us of the blood of the martyrs; white denotes purity, and green exuberant life. How much more expressive and lively the liturgy becomes when we try to discover the meanings of its formulas and rites."