Diffusion of Greek surnames: Alvanos (Albanian) vs Voulgaris (Bulgarian)
The program only maps the (up to) 20 communities with the highest concentration of the surname. I am sure there are more Alvanos in southern Greece and Voulgaris in northern Greece.
Armenis (Armenian) vs Kyprios (Cypriot)
Servos (Serb) vs (Mavrovouniotis) (Montenegrin)
Roumanos (Romanian) vs Vlachos (Vlach/Wallachian) vs Moldovanos (Moldavian)
Maltezos (Maltese) vs Gallos (French)
Sikelianos (Sicilian) vs Kalavros (Calabrian) vs Pouliezos (Pugliese)
Genovezos (Genovese) vs Lomvardos (Lombard)
Venetsianos (Venetian) vs Fourlanos (Friulian)
Ellinas (Greek endonym) vs Graikos (Greek exonym)
And finally..... Tourkos (Turk) vs Aravas (Arab)
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