I should note, it is virtually impossible to get this kind of data for countries other than the United States. If, in your reality, something is a constant, then you don't keep data on it. We don't have data for how often the sun rose in the East in 1066. There's no data. If I make the claim that the sun rose in the East all 365 days of the year 1066 AD, there is no hyperlink to back it up. Nonetheless, it is true.
Percentage of population belonging to a racial minority in 1790, the year of the birth of the United States of America:
USA: 19.3% racial minority (black). U.S. Census Bureau
UK: 0% [1]
France: 0%
Germany: N/A (Did not exist in 1790)
Prussia: 0%
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1. Wikipedia says there were maybe 40,000 Indians in the UK in 1850 (sixty years later) citing a journal article Excluding and Including “Natives of India”: Early-Nineteenth-Century British-Indian Race Relations in Britain. The total population of England alone in 1850 was 16.8 million, for a percentage racial minority of approximately 0.25%!!!)