The Portuguese language was developed gradually from the Vulgar language (i.e. Vulgar Latin) spoken in the countries which formed part of the Roman Empire and, both in morphology and syntax, it represents an organic transformation of Latin without the direct intervention of any foreign tongue.
The sounds, grammatical forms, and syntactical types, with a few exceptions, are derived from Latin, but the vocabulary has absorbed a number of Germanic and Arabic words, and a few have Celtic or Iberian origin.
Before the close of the Middle Ages the language threatened to become almost as abbreviated as French, but learned writers, in their passion for antiquity, re-approximated the vocabulary to Latin.
The Renaissance commenced a separation between literary men and the people, between the written and spoken tongue, which with some exceptions lasted until the beginning of the 19th century.
Then the Romanticists went back to tradition and drew on the poetry and every day speech of the people, and, thanks to the writings of such men as Almeida Garrett and Camilo Castelo Branco, the literary language became national once again.