Portuguese was evolved in the Western Iberian Peninsula from the spoken Latin language, from which all Romance languages descend, early in the 3rd century, in 218 BC, the Roman soldiers and colonists brought the languages there. The language began to distinguish itself from other Romance languages after the collapse of the Roman Empire, between 409 AD and 711; the Iberian Peninsula was invaded by the Barbarians in the 5th century. The newcomers, principally Suevi and Visigoths, rapidly absorbed Roman culture and the Vulgar Latin languages of the peninsula. After the Moorish incursion of 711, Arabic became the administrative language in the dominated regions, but most of the people continued to speak a form of Romance usually known as Mozarabic; so that when the Moors were defeated, the influence that they had applied on the language was small. Its major effect was in the lexicon.
In 1143, with the king Alfonso Henriques, Portugal became an autonomous country. In the first period of "Old Portuguese" - Portuguese-Galician Period, from 12th to the 14th century, the language came progressively into general use in the subsequent centuries, after earning popularity in the Christian Iberian Peninsula as a language for poetry. In 1290, the first Portuguese University (called the Estudo Geral) was created in Lisbon by the king Diniz; and decreed that Portuguese, then just named the "Vulgar language" (i.e. Vulgar Latin) should be called as the "Portuguese language" and should be formally used. It started to be used in written documents around the 9th century, and by the 15th century it had become a mature language with a rich literature.
Between the 14th and 16th century, the second period of “Old Portuguese” took place, with the Portuguese discoveries, the dialect was taken to various regions of Asia, Africa and the Americas (today, the great majority of Portuguese speakers live in Brazil, in South America). By the 16th century it had developed into a lingua franca in Asia and Africa, its use was not only for colonial administration and trade, but also for communication between local officials and Europeans of all nationalities. Its extend was helped by mixed marriages between Portuguese and local people, and by its connection with Roman Catholic missionary efforts, which led to the structure of a Creole called cristão ("Christian") in several parts of Asia and until the 19th century the languages continued to be popular. Some Portuguese-speaking Christian communities in India, Sri Lanka, Malaysia, and Indonesia conserved their language even after they were separated from Portugal. The language has mainly changed in these communities and has developed through the centuries into numerous Portuguese creoles; some still exist today, after hundreds of years in separation. Also, a significant number of words of Portuguese source are established in Tetum. Portuguese words introduced the lexicons of many other languages, such as Japanese, Indonesian, Malay, or Swahili.
In 1516, the end of “Old Portuguese” was marked by the publication of the Cancioneiro Geral de Garcia de Resende. The period of "Modern Portuguese" (from the 16th century to the present) saw an enlarge in the number of words of Classical Latin origin and erudite words of Greek origin borrowed into Portuguese during the Renaissance, which increased the complexity of the language.