Not as a normal occurrence, but in my (what I assumed would be casual) attempt at the African Power Kongo achievement, imagine my surprise when I finally popped my head onto the north coast of Africa, only to find Portugal owning all of Morocco, Algiers & Tunis. They had almost all of South America as colonies. They had Spain (having already integrated Aragon & Naples), France (having eaten happily on Burgundy, Low Countries & parts of Northern Italy) & Great Britain under them in PU's, basically dividing Central & North America between them. And they were the the leader of the HRE.
Because I had played the run super casual, I was not militarily equipped for anything even remotely close to a monstrosity of that size. It was super impressive and definitely the most blobby thing I have ever managed to see an AI achieve.