Across the world, Eustacius (Eustacius 
) is an extremely rare boy's first name.
| VARIANT | COUNTRY |
|---|---|
| Eustacius | Brazil, United States |
Efstathios, Eustac, Eustacchio, Eustace, Eustach, Eustache, Eustachio, Eustachy, Eustacio, Eustacjusz, Eustahije, Eustaqui, Eustaquio, Eustasio, Eustasius, Eustathios, Eustazio, Eustazy, Eustațiu, Eustácio, Eustáquio, Evstafy, Evstahij, Ostap, Stathis, Ευστάθιος, Στάθης, Астафий, Евстатий, Евстафий, Евстахий, Остап, Остафий, Стафей, Эсташ, Юстас, and Євстафій
| eustacius leodiensis composer in the princebishopric of Liège |
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