Spainish Empire was full race mixers but what is about British Empire? I am heard that British Empire was controlled by Rothschilds. Was ther laws agains race mixing like in USA?

If the British Empire race mixed, there would be no Britain today.

AFAIK no anti race-mixing law, just (most of) people not being brainwashed and totally stupid, as there was no pro-race mixing propaganda constantly pushed back then.