Agnusdei, very rare, would seem to be specific to the area between Lizzano and Manduria in the Taranto area, Sdei, typically Umbrian, of Perugia, Foligno and Trevi, it is probably the apheretic form, it should be one of the surnames originating from Catholic mercy and attributed to foundlings, but the connection with a nickname linked to a particularly devout behavior or to the habit of bringing blessed amulets called agnusdei in the past is not to be excluded.
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