* Historically: Spain is the origin of the Spanish language, so it's the first place where Spanish was spoken.
* Modernity: While Spain is the origin, it's not the largest Spanish-speaking country. That title belongs to Mexico.
* Independence: Spain was the first Spanish-speaking country to be independent as it was already an independent nation when the language developed.
So, it really depends on your perspective.
* If you're talking about the birthplace of the language, then Spain is the first.
* If you're talking about population or land area, then Mexico is the largest Spanish-speaking country.
It's important to remember that language evolves and spreads, so it's not always easy to pin down a "first" in these kinds of questions!