A standard joke about that: a dialect is an ideolect with a history and body of literature. A language is a dialect with an army and a navy. Language is an instrument of politics like any other.
Where my father grew up, the dominant language was not Spanish but Caló, which is generally (incorrectly, in my opinion) considered a degenerate form of Spanish. Later on he had to catch up a lot in order to be taken seriously in international business.
He also learned Brasilian Portuguese, which started out as a regathering of various dialects of Lisbon Portuguese. It is a defacto language, and may become be widely recognized as such, given the political weight behind it.
Where my father grew up, the dominant language was not Spanish but Caló, which is generally (incorrectly, in my opinion) considered a degenerate form of Spanish. Later on he had to catch up a lot in order to be taken seriously in international business.
He also learned Brasilian Portuguese, which started out as a regathering of various dialects of Lisbon Portuguese. It is a defacto language, and may become be widely recognized as such, given the political weight behind it.