Gustav

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A royal name in Sweden, traditionally explained (even by Gustav I Vasa himself) as Swedishgöt + staf "staff (=support) of the Geats (southern Swedes)". But there is no such name in Old Norse, and Gustav is more probably a Swedish rendering of Old Polish / north-west SlavicGostislav, from Proto-Slavic *Gostislavъ, from *gostь(“guest”) + *slava(“glory”).