Dejak families are Croats and they are mostly from Virovitica. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Virovitica.
Prevalence
About 90 people with faimily name Dejak live in Croatia today, in 30 households. There were 190 of them in the middle of the past century, and their number halved. They are located in 9 Croatian counties, in 10 cities and 8 other places, mostly in Zagreb (20), Donja Lomnica (<10), Nova Bukovica in Slatina area (<10), Split (<10), and in Rokovci in Vinkovci area (<10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over ten times, the first time 1923 in source Emigration Commission Zagreb.