Ольга is a feminine given name documented in Russian, Ukrainian and Old Ruthenian. English Wiktionary traces it to Old Norse Helga via Old East Slavic.
Old Norse origin
Source-reported
Inherited from Old East Slavic Ольга (Olĭga) (compare Оле́г (Olég)). The Belarussian version for Olga is Volha (Вольга).https://www.behindthename.com/name/volha The term Olga/Volha could be connected with the term for the Russian river Volga (Волга). Olga could also be connected to Old Norse Helga, from heilagr, from Proto-Germanic *hailagaz.
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