When attempting to explain the specificities of Brazilian Portuguese, scholars have made two main proposals. The first is based on the action of linguistic contact, with a more active participation of African and/or indigenous languages. The second argues that the linguistic changes that occurred in Brazilian Portuguese were already contained in the transplanted European language. The first formulation is associated with the hypothesis that Brazilian Portuguese underwent a period of creolization, some traces of which remain to this day (Baxter, 1992). This has been challenged by those who see the language spoken in Brazil as a continuation of the direction in which the European variety was evolving.  
The fact is that, in both Cuba and Brazil, the social situation favoured the learning and use of Spanish or Portuguese. This was true for both the Boçais, Africans with little or no command of the language of the colonizers, and the Ladinos, Africans who arrived in the American colonies already speaking Spanish or Portuguese, since they had learned these languages prior to their arrival, often during the relatively long periods Africans from different ethnic groups were forced to remain in the slave warehouses while the ships were being loaded.  
The debate that has developed on the interaction between African and European languages in Latin America has been based primarily on literary records and the reports of travellers, who often tended to caricature the way in which Africans tried to speak European languages. More recently, information has been sought in religious rites of African origin and in the study of the language of rural communities made up of Afrodescendants. Although there are many different sources, they all demonstrate, by varying degrees, the possible impact of interference from African languages. This is true both of lexical considerations (loans from African languages) and grammatical factors (above all, phonetic changes and agreement at odds with the cultural norms of Spanish and Portuguese).