Who was or were the first people that used spanish language?

It's impossible to pinpoint the *first* people who used Spanish. The language evolved over centuries, and there's no single person who "invented" it. However, we can trace its roots back to:

* Vulgar Latin: This was the everyday language spoken by Roman soldiers and colonists in the Iberian Peninsula (modern Spain and Portugal). Over time, it diverged from Classical Latin, the language of literature and government.

* Mozarabic: This was a Romance language spoken in the Iberian Peninsula under Muslim rule. It had a strong influence on the development of Castilian Spanish.

* Castilian: This dialect of Vulgar Latin emerged in the northern part of the Iberian Peninsula and eventually became the dominant language in Spain.

So, it wasn't a single person, but rather a gradual process of linguistic evolution involving:

* Roman soldiers and settlers who brought their language to the Iberian Peninsula.

* Local populations who interacted with the Romans and adopted and adapted their language.

* People living in different regions of the Iberian Peninsula, whose dialects eventually merged into Castilian.

The process of Spanish language development is complex and fascinating!