Korošec families are Croats and they are mostly from Koprivnica area. In the past century, relatively most of Croatian residents bearing this family name were born in Koprivnica and Zagreb.
Prevalence
About 260 people with faimily name Korošec live in Croatia today, in 120 households. There were 310 of them in the middle of the past century, and their number decreased by 20 percent. They are located in the most of Croatian counties, in 25 cities and 31 other places, mostly in Zagreb (60), Koprivnica (25), Sisak (20), Zablatje in Koprivnica area (15), and in Rijeka (15).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over twenty times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.