Poljak families are usually Croats and they are mostly from Sinj. According to some sources they are from Ogulin area, very rarely Serbs. In the past century, relatively most of Croatian residents bearing this family name were born in Sinj and Zagreb. In Glavice in Sinj every fifth inhabitant had the family name Poljak.
Prevalence
About 3400 people with faimily name Poljak live in Croatia today, in 1400 households. There were 2700 of them in the middle of the past century, and their number increased by 30 percent. They are located in all Croatian counties, in 88 cities and 249 other places, mostly in Glavice (595), Zagreb (470), Sinj (180), Split (175), and in Bregi Radobojski in Krapina area (105).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over sixty times, the first time 1750 in source 18th Century Census.