What was the first Spanish-speaking country?

There isn't a single, definitive answer to this question. It depends on how you define "Spanish-speaking country."

Here's why:

* Castilian is the origin: The Spanish language originated in Castile, Spain, and evolved from a variety of Romance languages.

* Colonization and expansion: During the Spanish colonial period, Castilian spread to the Americas, parts of Africa, and Asia.

* Independent nations: Many of these territories gained independence and established themselves as independent nations with Spanish as their official language.

Therefore, there's no single "first" Spanish-speaking country. Some argue it could be:

* Spain itself: As the origin of the language, Spain has been a Spanish-speaking nation for centuries.

* Dominican Republic: Some consider it the first Spanish colony in the Americas, though other colonies existed simultaneously.

Ultimately, the question of the "first" Spanish-speaking country is a matter of perspective and interpretation.