In Croatia, Hiljak families are Croats (from Novi Marof ).
Prevalence
Only a few people with faimily name Hiljak live in Croatia today, in one household only. There were 0 of them in the middle of the past century, and their number remains constant. They are located in one Croatian city only, in Novi Marof (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over five times, the first time 2007 in source Encyclopaedia of Croatian Surnames.