you could just follow ancient population genetics, as if it hadn't been already done and done beyond doubt there have not been "massive" migrations for the most part between europe and the levant after the last 8000 years except during the roman empire and mostly anatolia -> south europe samaritans/lebanese/palestinians are obviously much more native than ashkenazi, who are maybe 30% directly ancient levantine then again the english too identify as anglo despite being only also approx 30% anglo-saxon
Italy