I know Latin was a vulgarization in attempting to make Mass more accessible to Christians. So which were the languages used in paleo-Christian Mass? Koine Greek, classical Greek, or something else? What other languages were used, up until the Council of Trent.
In the earliest centuries of the Church, there wasn't a pattern of using liturgical languages, as much as trade languages.
In the East, Greek was predominantly used because whereas it was the first language of few people, it was a second language for many people. It's use could symbolize the internationality of the Church, but more practically, it made it possible for as many people as possible to follow along, if not understand every word. Interestingly enough, Greek predominated in Rome itself, because its heavily international population didn't all speak Latin. By contrast, in North Africa, Latin seems to have been the predominant language almost immediately. Outside of Egypt, Latin was the language of international affairs in North Africa because of its extensive colonization and coordination by Roman authorities. This was also the case in Spain, Britain, and non-Mediterranean France, other regions little influenced by the Greeks. When it was evangelized, Ireland experienced the Mass in Latin. (Nickerson, Jane Soames. A Short History of North Africa. New York: The Devin-Adair Co., 1961, p30.)
In the ninth century, permission was given by the Church to translate the Mass and related texts (such as the scripture) into what is now called Old Church Slavonic. At the time, it was a dated but not quite defunct legal and ceremonial language used in Slavic regions, essentially a mother language to the languages they were speaking at the time. The idea was the same - a single liturgical language for a broad swath of country and for many nations, not exactly native to any of them, but not entirely foreign, either. (Korolevsky, Cyril. Living Languages in Catholic Worship: An Historical Inquiry, trans. Donald Attwater. Westminster, Maryland: The Newman Press, 1957, p3.)
Additionally, Franciscan missionaries to the Mongols were given permission to translate the liturgical rites and the sacred scripture into their language in the 13th or 14th century, provided that the most noble and poetic version of the language be used. In like manner, Jesuits were given permission to translate the same materials into Chinese (Mandarin, I think) in the 16th-17th century, but because of the cultural climate in Europe at the time, they never actually made use of these permissions.
So long answer shortened: Latin was in use in the early Church but, ironically enough, not in the region of Latin's origin. The Church's primary concern was not exactly just that the Mass should be accessible. She was also concerned that the Mass should be transnational.
If you're wondering, while in the seminary, I wrote a paper on topic of liturgical and vernacular language in pre-Christian and Christian worship. My thesis is that the Church has always wanted both accessibility and transcendence in the worship of a God who transcends and makes himself accessible. (Here's a dropbox link. It doesn't seem like a very good way to share the file, but I don't think there's a place to upload or attach PDFs here: Vernacular and Liturgical Language in the Mass
What languages were used during Mass from paleo-Christianty until the Council of Trent?
I know that the Tridentine Mass was always said in Latin, but have there ever been exceptions to this rule? I heard that some exceptions were allowed!
If we count the lawful liturgical variants of the Tridentine Mass such as the Dominican Rite and the Carmelite Rite and permission given to some Religious Orders, we able to see that the Holy See has given various indults for the Tridentine Mass to be celebrated in various languages.
Although Latin prevails in the West as a unified liturgical language, in the face of certain circumstances the Roman church has made exceptions to provide a language in the Liturgy more familiar to the people. It is in the ninth century among the Slavic nations that we find a departure from liturgical Latin in divine worship. A privilege was first granted to Sts. Cyril and Methodius, by Pope Hadrian II in 869, and again by Pope John VIII in 880 to use the vernacular (Slavonic) in the Liturgy.
Another example of the flexibility of which the Roman rite is capable is the privilege granted for the use of Chinese as a liturgical language. History records in the fourteenth century that the first Franciscan missionary to China, John of Monte Corvino, used the vernacular in the Liturgy.26 Pope Paul V, in a brief of June 27, 1615, granted the same privilege to Jesuit missionaries. As recently as 1949, the privilege to use the Chinese literary language in the Liturgy was granted by the Holy Office.
Still further concessions have been granted:
a) During the fourteenth century the Roman Liturgy in its Dominican variant was translated into Greek for use by the Dominican missionaries in Greece.
b) Permission had been granted to celebrate the Dominican Liturgy in the Armenian classical language in Armenia.
c) At the end of the sixteenth century missionaries of India of the Latin rite were allowed to celebrate Mass in Syriac.
d) In the seventeenth century the Discalced Carmelites were granted permission to use Arabic in their mission foundation in Persia.
e) In the seventeenth century the Theatine Clerics were granted permission to use Georgian or Armenian in their mission foundation in Georgia.
f) In the nineteenth century the Franciscans in the Holy Land were granted permission to use Arabic.
g) In 1958, an indult was granted India to use Hindi.
h) Five Latin priests in the Holy Land were granted permission to use Hebrew.
i) In 1959, the Holy See renewed Germany's privilege to use the vernacular (German) in the Epistle and Gospel after they are recited in Latin. - Liturgical Languages
Certainly the Apostles said mass in Hebrew and Aramaic. The apostolic times predates the times prior to times that liturgical rites were distinguished from one anther.
The first language of Christian liturgy was Aramaic, the common language of the first Christians, who were Palestinian Jews. While Hebrew was the language of scripture and formal worship, Christian worship occurred in the home where Aramaic was spoken. The words Abba and maranatha are Aramaic.
Christianity quickly spread from Palestine to the rest of the world, and the Eucharist came to be celebrated in many languages, including Syriac, Coptic, and Armenian. In most of the Mediterranean world, the common language was Greek, which became the language of liturgy in that region and remained so until the early third century.
From around the third century B.C., what we call “classical” Latin was the language of the Roman aristocracy and the educated classes. Around the time Jesus was born, during the reign of Augustus Caesar, the language began to change. The Roman aristocracy was destroyed by war and political infighting; when they disappeared, their language went with them. Classical Latin was replaced by a less refined version of the language.
In the third and fourth centuries A.D. this form of Latin began to replace Greek as the common language of the Roman world and soon became the language of the liturgy.
Exactly how this change in the liturgy came about is uncertain. In the early church the liturgy was led extemporaneously by the bishop, according to a pattern. There were written examples of Eucharistic Prayers, but they were models, not prescribed prayers. The last such document in Greek was written around the year 215. By the sixth century, the Roman Canon (which is still in use, also called Eucharistic Prayer I) appears, completely in Latin and prescribed for use exactly as written. - When did we start celebrating Mass in Latin?
Up to the third or fourth century, the mass in Rome was in Greek, not Latin. Some believe that this was strongly influenced by St. Augustine of Hippo.