You're correct...a sense of "Somaliness" is pretty new to Somalis, just like being an "Ethiopian" "Eritrean" or lol, "Djiboutian" are all new.
The second term historically used to describe Europeans was Ferenji, which was basically a borrowing from the Islamo-world's habit of describing alll Crusaders by the blanket term "Franks". I think this is the term used for Europeans to this day in Ethiopia.
When I went to the States, I noticed a distinct change, where African Americans almost ALWAYS saw me as Black, (even AfrAm) and would refer to me as 'my brutha' etc. While Whites were more along the lines of 'You're brown' or some kind of Muslim'' as if its an ethnic/racial group.