Košćak families are Croats and they are mostly from Novi Marof. In the past century, relatively most of Croatian residents bearing this family name were born in Varazdin and Novi Marof. In places Strmec Remetinečki and Oštrice in Novi Marof every eighth inhabitant had the family name Košćak.
Prevalence
About 600 people with faimily name Košćak live in Croatia today, in 280 households. There were 290 of them in the middle of the past century, and their number doubled. They are located in the most of Croatian counties, in 35 cities and 71 other places, mostly in Zagreb (75), Varazdin (75), Ostrice (75), Remetinec (55), and in Novi Marof (25).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over sixty times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.