Asklemmy

Different heritage, but very much considered black. Australia has a whole racist history that marginalises indigenous Australians explicitly on their blackness...

Yeah it blew my mind when a few times I was called black in Australia when I am of Indian heritage. One even made a joke about my penis being larger!

In Britain, Asian means someone from Indian/Pakistani part of area of Asia, whereas in North America and Australia it means Chinese/Japanese parts of Asia.

Blackness/Whiteness is an interesting concept - it's remarkably fluid, especially with changes in time and place. Race isn't the same as ethnicity or genetics, or a direct result of it, although racists often try to claim it is - a stark example of this in Western societies like the US and Australia would be how they categorize Italian and Greek peoples, Slavic peoples, or ethnically-Jewish peoples - the idea of whether or not each of these is White has largely shifted over time, often as a group stops being the current biggest immigration demographic. The USA even had a concept of "Black Irish", which originally meant a post-Famine Irish refugee. Human races are ultimately just social classes, not a biological concept.

Another aspect, related to this thread, is hypodescent. In some societies (it's not a universal thing!), if a child has a Black parent and a White parent, is the child Black or White, or another label entirely? As mentioned in that article, some US states used to legally define someone as Black even if only 1 of their 16 great-great-grandparents were Black.