Cape Verdean Creole (also known as Kabuverdianu) a language spoken on the islands of Cape Verde and is a Portuguese-based creole. Virtually all Cape Verdeans speak the language and is used as a second language by the Cape Verdean diaspora.
The language has particular importance for creolistics studies since it is the oldest (still-spoken) creole. It is the most widely spoken Portuguese-based creole language.
It is difficult to trace the history of Cape Verdean Creole due to a lack of written documentation and to ostracism during the Portuguese administration of Cape Verde.
There are presently three theories about the formation of Creole. The monogenetic theory claims that the creole was formed by the Portuguese by simplifying the Portuguese language in order to make it accessible to African slaves. That is the point of view of authors like Prudent, Waldman, Chaudenson, Lopes da Silva. Authors like Adam and Quint argue that Creole was formed by African slaves using the grammar of Western African languages and replacing the African lexicon with the Portuguese one. Linguists like Chomsky and Bickerton argue that Creole was formed spontaneously, not by slaves from continental Africa, but by the population born in the islands, using the grammar with which all human beings are born; this would explain how creoles localized several miles away have similar grammatical structures, even though they have a different lexical basis.
According to A. Carreira, Cape Verdean Creole was formed from a Portuguese pidgin, on the island of Santiago, starting from the 15th century. That pidgin was then transported to the west coast of Africa by the lançados. From there, that pidgin diverged into two proto-Creoles, one that was the base of all Cape Verdean Creoles, and another that was the base of the Guinea-Bissau Creole.
Cross referencing information regarding the settlement of each island with the linguistic comparisons, it is possible to conjecture some conclusions. The spreading of Cape Verdean Creole within the islands was done in three phases:
In a first phase, the island of Santiago was occupied (2nd half of the 15th century), followed by Fogo (end of the 16th century).In a second phase, the island of São Nicolau was occupied (mostly in the 2nd half of the 17th century), followed by Santo Antão (mostly in the 2nd half of the 17th century).In a third phase, the remaining islands were occupied by settlers from the first islands: Brava was occupied by population from Fogo (mostly in the beginning of the 18th century), Boa Vista by population from São Nicolau and Santiago (mostly in the 1st half of the 18th century), Maio by population from Santiago and Boa Vista (mostly in the 2nd half of the 18th century), São Vicente by population from Santo Antão and São Nicolau (mostly in the 19th century), Sal by population from São Nicolau and Boa Vista (mostly in the 19th century).
In spite of Creole being the first language of nearly all the population in Cape Verde, Portuguese is still the official language. As Portuguese is used in everyday life (at school, in administration, in official acts, in relations with foreign countries, etc.), Portuguese and Cape Verdean Creole live in a state of diglossia. Due to this overall presence of Portuguese, a decreolization process occurs for all the different Cape Verdean Creole variants.