Eustacchi, very rare, has a Roman and a Marche lineage, Eustacchio is very rare, it would seem from northern Italy, it should derive from the late Latin name Eustachius, we remember: "... Beatissimus Christi martyr Eustachius quondam secundum saeculum manens insignis honore et meritis praecellebat cunctis ... ", of the use of this name in medieval times, around 1000 we have this example:" ... Appropinquante autem hora scilicet in qua Dominus noster Iesus Christus dignatus est pro nobis sufferre patibulum crucis, our milites fortiter pugnabant in castle , uidelicet dux Godefridus, et comes Eustachius frater eius ... ", we find traces of these surnames in Arona (VB) in the second half of the 1400s with Francesco De Eustacchi, commendatory abbot. additions provided by Giovanni Vezzelli Eustacchi is the surname of the personal name Eustachio, from the Greek 'eu - stachys' = 'abundant ears of corn'. It would therefore have a similar meaning to 'fruitful'.
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