system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why did Latin stop being commonly-spoken while its derivations remained?
gpt
I'd say what key is that its not that its derivations remained, its that they developed.

The roman empire was massive. But it feel, with Latin being the dominant language all over.

Now when it collapsed it broke into separate kingdoms. With time comes change. However the kingdoms would not change uniformly. The comparative isolation meant local dialects began to evolve into new languages with a common base.

Now add in that they each had to deal with outside political forces. The Spanish had more north africans to deal and trade with meaning they would be more affected by them than the eventual french would be by their respective non-latin neighbours. Over time they all developed differently, creating derivations.