Šupak families are Croats and they are mostly from Rijeka area. In the past century, relatively most of Croatian residents bearing this family name were born in Rijeka and in Rijeka area. In Ilovik in Rijeka area every third inhabitant had the family name Šupak.
Prevalence
About 70 people with faimily name Šupak live in Croatia today, in 40 households. There were 80 of them in the middle of the past century, and their number decreased by 10 percent. They are located in threee Croatian counties, threee cities and 13 other places, mostly in Rijeka (30), and in Grobnik (25), Cavle (<10), Brnelici (<10) and Martinovo Selo (<5) in Rijeka area.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 2007 in source Encyclopaedia of Croatian Surnames.