Honestly, I never understood the difference.
Studying the Colonial era and the Independence of Brazil, Portuguese leaders were referred as the Portuguese kings, while post-independence the Brazilian Empire started and the leaders of the country were called Emperors (not kings).
But I don’t really know what makes a place a Kingdom (in Portugal’s case during colonial times) or an Empire (Brazil between 1822-1889). In practice they sound like the same thing, working in the same way.
The difference is only regarding expansionism (If you govern only your people = Kingdom, govern other places = Empire). But that never made sense to me because then UK isn’t really a Kingdom like people talk, it’s an Empire. Same thing with all these European monarchies which expanded through colonialism in the sea exploration period.
In Brazil case it made sense to be called Empire because well, most of the people who lived here and were ethnically entitled to be the “Real Brazilians” had been murdered in the centuries prior, the Indigenous. So both the people being governed and the monarchy had no place of calling itself a “Kingdom” in a land so ethnically diverse post-colonial years. Even if they happened to be born here and be Brazilian for all effects.
Calling itself an empire was also strategy of showing Portugal there wouldn’t be any continuity to their kingdom government. That’s why to me it sounds like people just randomly choose the terms and “king” and “emperor” are in practice interchangeable terms.
Would you say this for the Portuguese words too?
