In Croatia, Kvas families are generally Croats (from Cabar ), very rarely Serbs, and barely Slovenes. In the past century, relatively most of Croatian residents bearing this family name were born in Cabar and Vinkovci.
Prevalence
About 50 people with faimily name Kvas live in Croatia today, in 30 households. There were 40 of them in the middle of the past century, and their number increased by 20 percent. They are located in 10 Croatian counties, in 11 cities and 7 other places, mostly in Vinkovci (20), Cabar (<10), Osijek (<5), Vukovar (<5), and in Zadar (<5).