Čujko families are Croats and they are mostly from Zapresic area. In the past century, relatively most of Croatian residents bearing this family name were born in Karlovac and Zagreb. In Zdenci Brdovečki in Zapresic area every ninth inhabitant had the family name Čujko.
Prevalence
About 130 people with faimily name Čujko live in Croatia today, in 50 households. There were 180 of them in the middle of the past century, and their number decreased by 30 percent. They are located in four Croatian counties, four cities and 9 other places, mostly in Sisljavic (45), Prigorje Brdovecko in Zapresic area (30), Zapresic (15), Karlovac (10), and in Zagreb (<10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 2007 in source Encyclopaedia of Croatian Surnames.