I think the surname Svombo is of Southern Slavic origin, ultimately of Proto-Slavic, and possibly could be of Serbo-Croatian. The etymology of Svombo is identical to the etymology of Svoboda, meaning "freedom". The people who originally bear this surname migrated to Greece and became the name Σβομπος, like you said. I think this surname Svoboda also migrated to France and Scandinavia, also changing its form, possibly Sobo, Sabo, Sambo, Sombo, and others. This explains why the surname Svombo and the Greek form are so rare, because the surname has spread across Europe becoming variants, taking different forms. Now, when the French people pronounced Svoboda, it sounds like Swomboda. This is also true with the Scandinavians, pronouncing it "Sombos" instead of "Sobos". I think the Svombos was influenced by the French or Scandinavians before coming into the UK. I think Nickolas Svombo departed from France, or Norway, and there, Nickolas had his surname changed according to them and how they pronounced it. From France or Norway, Nickolas was originally from Greece, possibly didn't have the form of "mb" until he came to France or Norway first, before coming to England.
Now, I hypothesize that the Faroes Svabo and the Norwegian Svabø are too of the same origin. I'll have to look into them further though.
This message was edited by the author on July 26, 2012 at 1:51 PM