What the heck?

The Catalonians also had one https://en.wikipedia.org/wiki/Terra_Lliure

And Terra Lliure would have been a joke if not for the only innocent death they provoked. It is perhaps the only terrorist group that has more deaths by accident than actions they tried to do

The UK.

France.

Germany.

The USA.

The list of "[countries] patched together from previously autonomous bodies" happens to be an incredibly huge subset of countries that exist today.

I can't think of any country that has remained exactly the same throughout history. Nearly every country out there is either an agglomeration of formerly independent entities or used to be part of a bigger entity at some point.

Your categories are useless. Unless you're trying to define categories for countries which don't exist.

The USA is no remant, they earned their independence. I don't quite get the "composed of one" part.