In the words of Brazilian tupinologist Eduardo Navarro, "it is the classical indigenous language of Brazil, and the one which had the utmost importance to the cultural and spiritual formation of the country".

In the early colonial period, Tupi was used as a lingua franca throughout Brazil by Europeans and Amerindians, and had literary usage, but it was later suppressed almost to extinction.

[2][3] Old Tupi was first spoken by the Tupinambá people, who lived under cultural and social conditions very unlike those found in Europe.

It is quite different from Indo-European languages in phonology,[citation needed] morphology, and grammar, but it was adopted by many Luso-Brazilians born in Brazil as a lingua franca.

Until the 16th century, these languages were found throughout nearly the entirety of the Brazilian coast, from Pará to Santa Catarina, and the Río de la Plata basin.

Today, Tupi languages are still heard in Brazil (states of Maranhão, Pará, Amapá, Amazonas, Mato Grosso, Mato Grosso do Sul, Goiás, São Paulo, Paraná, Santa Catarina, Rio Grande do Sul, Rio de Janeiro, and Espírito Santo), as well as in French Guiana, Venezuela, Colombia, Peru, Bolivia, Paraguay, and Argentina.

José de Anchieta reportedly wrote more than 4,000 lines of poetry in tupinambá (which he called lingua Brasilica) and the first Tupi grammar.

In the second half of the 18th century, the works of Anchieta and Figueira were republished and Father João Filipe Bettendorff wrote a new and more complete catechism.

When the Portuguese Prime Minister Marquis of Pombal expelled the Jesuits from Brazil in 1759, the language started to wane quickly, as few Brazilians were literate in it.

A new rush of Portuguese immigration had been taking place since the early 18th century, due to the discovery of gold, diamonds, and gems in the interior of Brazil, and these new colonists spoke only their mother tongue.

Old Tupi survived as a spoken language (used by Europeans and Indian populations alike) only in isolated inland areas, far from the major urban centres.

When the Portuguese first arrived on the shores of modern-day Brazil, most of the tribes they encountered spoke very closely related dialects.

While this structure is not optimal, it certainly served its purpose of allowing its intended readership (Catholic priests familiar with Latin grammars) to get enough of a basic grasp of the language to be able to communicate with and evangelise the natives.

Also, the grammar sometimes regularised or glossed over some regional differences in the expectation that the student, once "in the field", would learn these finer points of the particular dialect through use with his flock.

This led to a Brazilian pun about this language, that native Brazilians não têm fé, nem lei, nem rei (have neither faith, nor law, nor king) as the words fé (faith), lei (law) and rei (king) could not be pronounced by a native Tupi speaker (they would say pé, re'i and re'i).

Scientific reconstruction of Tupi suggests that Anchieta either simplified or overlooked the phonetics of the actual language when he was devising his grammar and his dictionary.

It is easily typed with regular Portuguese or French typewriters and computer keyboards (but not with character sets such as ISO-8859-1, which cannot produce ẽ, ĩ, ũ, ŷ and ỹ).

In addition, verbs can represent a present, past, or future action because, unlike Portuguese, they do not express time.

Some examples: To express something happening in the future, the clitic -ne is always added to the last word in the sentence, independent of its grammatical class.

Here are some examples with their explanations: (Child is pitanga) (from ybytyra, mountain) In Old Tupi, there are only numerals from one to four, both cardinal and ordinal, as the need for mathematical precision was small in a primitive economy.

The two types could be used alone or combined in transitive clauses, and they then functioned like subject and object in English: Although Tupi verbs were not inflected, a number of pronominal variations existed to form a rather complex set of aspects regarding who did what to whom.

That, together with the temporal inflection of the noun and the presence of tense markers like koára "today," made up a fully functional verbal system.

The notion of plural was also expressed by adjectives or numerals: Unlike Indo-European languages, nouns were not implicitly masculine except for those provided with natural gender: abá "man" and kuñã[tã] "woman/girl"; for instance.

Adjectives and nouns, however, had temporal inflection: That was often used as a semantic derivation process: With respect to syntax, Tupi was mostly SOV, but word order tended to be free, as the presence of pronouns made it easy to tell the subject from the object.

Nevertheless, native Tupi sentences tended to be quite short, as the Indians were not used to complex rhetorical[citation needed] or literary uses.

Old Tupi literature was composed mainly of religious and grammatical texts developed by Jesuit missionaries working among the colonial Brazilian people.