The origins of which lie in 'old English' customs, which isn't racist

Racism is the oldest traditional English custom of them all. And bugger the origins - which are always spurious fakelore anyway. No one blacking up in today's cultural climate can do so entirely innocent of the racist implications of such a noxious act.

As someone said (I forgot who!) the true origin of any Folk Custom is only the last time it was performed; the time before that is part of a different continuity already lost in the mists of time.