753 BC Traditional date of the founding of the city of Rome by Romulus, a fictional character who killed his twin brother Remus, populated his city with escaped convicts, and found wives for his subjects by kidnapping Sabine women who had come for a visit. At this stage, Latin is the language spoken by several thousand people in and near Rome.
6th century BC Earliest known Latin inscription, on a pin, which says "Manios me fhefhaked Numasioi", meaning "Manius made me for Numerius". Only a few other inscriptions predate the 3rd century BC.
250-100 BC Early Latin. The first Latin literature, usually loose translations of Greek works or imitations of Greek genres, stems from this period. Meanwhile, the Romans are conquering the Mediterranean world and bringing their language with them.
100 BC-150 AD Classical Latin. Guys like Cicero, Caesar, Vergil, and Tacitus write masterpieces of Latin literature. Also, Ovid writes a book on how to pick up women at the gladiator shows. The literary language becomes fixed and gradually loses touch with the ever- changing popular language known today as Vulgar Latin.
200-550 Late Latin. Some varieties of literature adhere closely to the classical standard, others are less polished or deliberately closer to the popular speech (e.g., St. Jerome's translation of the Bible into Latinthe Vulgate). The western half of the empire is falling to pieces, but the Greek-speaking east, which is still in good shape, keeps using Latin in official contexts until the end of this period.
600-750 Latin has become a dead language. Few people in the west outside of monasteries can read. The spoken languages of Italy, France and Spain change rapidly. Monks, particularly in Ireland, read and write classical Latin and preserve ancient texts as well as church documents. The Roman Catholic church continues to use Late Latin in the liturgy, though they eventually decide to deliver homilies in the local popular language. The Byzantines still call themselves Romans but have given up on the Latin language.
800-900 The Carolingian Renaissance. Charlemagne decides that education is a good thing and promotes it in his kingdoms. After his death scholarship goes downhill a while, but never as far as it had before his reign.
1100-1300 Contact with the educated Arabs who have conquered North Africa and Spain leads to a revival of learning, especially the study of Aristotle and other Greeks. Leading smart guys include St. Thomas "The Dumb Ox" Aquinas and John "Dunce" Scotus, as well as Petrus Hispanus, a pope who was killed when a ceiling collapsed on him. All learned writing is done in Latin, a practice which persisted until the 20th century at some fairly silly universities.
Mid 14th century The Black Death kills a lot of people, including students, professors and other people who live in crowded, unsanitary cities. This is bad for the educational system. Meanwhile, an Italian poet named Petrarch decides that plague-infested professors and anyone else who doesn't write the classical Latin used by Cicero is a moron. In fact, everyone between Cicero and Petrarch was a moron in the latter's opinion, so it was high time to have a Renaissance and make fun of everything medieval.
1400-1650 During the Renaissance, which spreads from Italy to France and finally to England, people start reading Latin classical authors and bringing Latin words into their languages. In England, this is called "aureate diction" and is considered evidence of great learnedness. Furthermore, as science develops, Europeans find it useful to have a universal Latinate terminology to facilitate international research.
up till 1900 Almost everyone who goes to college has to learn Latin, and most humanities majors have to study Greek as well. Many of the Latin roots borrowed during the aureate diction period have come to seem native and can be used in forming new words.
mid 1960s The Catholic Church decides that Latin is no longer the obligatory language of Catholic liturgies. Meanwhile, what with free love and everything, most young people of the 60s figure they have better things to do than learn Latin.
Today Nobody speaks Latin well, and few people can write it, but lots can read it. Many of them are tenured professors, so they'd be hard to get rid of even if we wanted to.