A "news" story has surfaced today that an African-Australian has discovered that some of Australia's early immigrants had African heritage. In particular, she is excited that John Harvey who immigrated to South Australia in 1839 (three years after the colony was established) had African descent. This appears to be derived from a line in his obituary that "His father was a native of St. Helena, and returned with Lord Duffis."
St Helena is described as "an island off of South Africa" without mentioning that it is 1950 km off the coast and appears to not have had any indigenous population before European discovery in 1502.
The obituary (written in 1899) says John was born in Wick, County Caithness on July 22, 1821. It doesn't name his father, and I can't find a "Lord Duffis", but have found "Lord Duffus" with no indication that any of them had been to St Helena.
I'm seeking clarification of whether "native of St Helena" means "African heritage" or is just as likely that he was a wealthy former slave owner who funded his son's education and colonial exploits.