Where does “Київська Русь” come from?

Київська Русь (Ukrainian) comes from Ukrainian Русь, from Old East Slavic Русь, from Finnish ruotsi, from Proto-Finnic *roocci, from Old Swedish roþs-, from Old Norse róðr, from Proto-Germanic rōþrą, from Proto-Indo-European h₁reh₁- — to row; to separate; loose, sparse, rare.

Ancestry of “Київська Русь”, step by step

Київська Русь traces back through two separate lines of ancestry.

via Ukrainian Русь

StepLanguageWordMeaning
1UkrainianРусьRus
2Old East SlavicРусьRus; Ruthenia
3FinnishruotsiSwedish
4Proto-Finnic*roocciSwede originally anyone from Roslagen
5Old Swedishroþs-related to rowing
6Old Norseróðrrowing
7Proto-Germanicrōþrąoar; rudder
8Proto-Indo-Europeanh₁reh₁-to row; to separate; loose, sparse, rare

via Ukrainian київський

StepLanguageWordMeaning
1UkrainianкиївськийKyiv/Kiev, Kyivan/Kievan, Kyivite
2Ukrainian-ськи́йUsed to form adjectives, often from nouns; -ish, -y, of -'s (double genitive)
3Proto-Slavic-ьskъ-ic, -ish
4Proto-Indo-European-iskosCharacteristic of, typical of, pertaining to
Every word from Proto-Indo-European h₁reh₁- →Every word from Old Swedish roþs- →Every word from Proto-Finnic *roocci →