Εὐμένης (Ancient Greek) comes from Ancient Greek εὖ, from Ancient Greek ἐΰς, from Proto-Hellenic ehu-, from Proto-Indo-European h₁su-, from Proto-Indo-European h₁wes- — good; to be cheerful, happy; to eat, to feast.
Ancestry of “Εὐμένης”, step by step
Εὐμένης traces back through 3 separate lines of ancestry.