Alagna would seem typically Sicilian, especially from Trapani, Marsala and Mazara del Vallo, with an important nucleus also in Palermo, it could be a surname of ethnic derivation and indicate a Germanic origin of the founders or as a contraction of the name Alemagna (Germany) or as distortion of the term alani and therefore indicate the belonging of the progenitors to that people, a connection with the toponyms Alagna of Vercelli or Pavia is highly unlikely.
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