The vast majority of Brazilians speak only one language: the Portuguese language. You can find tribes in Brazil where people speak some sort of Indigeneous language as first language and also collonies where people speak European languages such as German, Italian and Japanese as first language, but those are exceptions. The language diversity that you can find in Brazil is especially about the different variants of Brazilian Portuguese - the variety of accents and regional terms that exist across the country is really remarkable. As far as culture is concerned, I would say that Brazil is really diverse. As it happens in other countries with a large territory and a vast population, the culture from state to state may vary significantly, and it can be noticed in the different types of food, local festivals and folklore that you can find in the different states of our nation. In conclusion, Brazil may not be so diverse regarding languages, but it's definitely diverse regarding the culture.