Fitzsimmons, Wilde and Lennox Lewis are the top 3. Conteh, Buchanan, Ted Kid Lewis, Turpin etc., deserve a mention well before the likes of Hamed, Hatton or Calzaghe.
he was aware of the fact that he was eligible to apply for british citizenship and he was pragmatic enough to realise that winning a british title would help launch his career. he took full advantage of this anamoly. it was quite a shrewd move. by the way - i also give lewis the nod..