In Croatia, Šiljac families are Croats (from Ozalj ). In the past century, relatively most of Croatian residents bearing this family name were born in Karlovac and Ozalj.
Prevalence
About 50 people with faimily name Šiljac live in Croatia today, in 20 households. There were 20 of them in the middle of the past century, and their number more than doubled. They are only located in in 7 Croatian cities and 5 other places, mostly in Karlovac (15), Sveticko Hrasce (10), Rijeka (<10), Priselci (<10), and in Hreljin (<10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1935 in source Emigration Commission Zagreb.