In Croatia, Kais families are predominantly Croats (from Serbia ), rarely Serbs. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Rijeka.
Prevalence
Only a few people with faimily name Kais live in Croatia today, in four households only. There were 10 of them in the middle of the past century, and their number remains constant. They are located in one Croatian city only, in Zadar (<10).