In Croatia, Cernjak families are predominantly Croats (from Klanjec area ), rarely Jews (from Zagreb ). In the past century, relatively most of Croatian residents bearing this family name were born in Klanjec area and in Dubrovnik.
Prevalence
About 10 people with faimily name Cernjak live in Croatia today, in five households only. There were 20 of them in the middle of the past century, and their number halved. They are located in only threee Croatian places: in Zagreb (<10), and in Ivanic Miljanski (<10) and Miljana (<5) in Klanjec area.
In the sources analysed in the project Acta Croatica so far, the name is mentioned over thirty times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.