Dubac families are frequently Croats and they are mostly from Slavonski Brod area , less frequently Italians (from Buje ). In the past century, relatively most of Croatian residents bearing this family name were born in Slavonski Brod and in Slavonski Brod area.
Prevalence
About 70 people with faimily name Dubac live in Croatia today, in 30 households. There were 60 of them in the middle of the past century, and their number increased by 30 percent. They are located in 7 Croatian counties, in 7 cities and 9 other places, mostly in Bukovlje in Slavonski Brod area (30), Martincici in Buje area (<10), Slavonski Brod (<10), Nova Gradiska (<10), and in Zagreb (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1930 in source Emigration Commission Zagreb.