Ethnic groups ( i.e, none Europeans or Americans) in the western world are asking the dominant majority to acknowledge the ethnic cultures
'Ethnic' doesn't and shouldn't mean 'minority group' or black. Everyone has ethnicity and an ethnic culture.
When these threads come up, the examples and discussion are so often American or about America that it is a bit depressing, and can be misleading. For example, I know that in America employers can be very repressive in relation to people of African descent having braids and other natural (i.e. not chemically processed hair styles). I don't know of the same thing happening here on remotely the same scale.
Debri's very good post at 22:15:03 is about the US entirely, and many people know more about that history that anything specific to the UK or the Empire. I think that's not only a real shame, but something that has real consequences in the present day.
Slavery was unenforceable in England and Wales at least, from 1772 and abolished throughout the Empire, with small exceptions, in 1833 (1843 in India).
As far as I can tell, none of the various Reform Acts exempted black people so black male householders would have got the vote in 1865, black women got the vote with their white counterparts in 1928. The first Indian MP was Dadabhai Naoroji in 1892, the first MPs of African descent were Bernie Grant, Diane Abbot and Paul Boateng in 1987.
Inter-racial marriage was never illegal, I think.
There were few if any laws enshrining discrimination in British law. That didn't stop it happening, but it did mean that the struggle to be treated fairly and equally was very different.
It also means that sensitivity to things like cultural appropriation tends to be different.