In Croatia, Koska families are generally Croats (from Backa, Vojvodina ), very rarely Hungarians (from Zagreb ). In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Kosovo.
Prevalence
About 20 people with faimily name Koska live in Croatia today, in 9 households. There were 0 of them in the middle of the past century, and their number multiplied. They are located in only five naselja i to in Zagreb (15), Dugo Selo (<5), Sesvete (<5), Pula (<5), and in Makarska (<5).