In Croatia, Željko families are Croats (from Ozalj ). In the past century, relatively most of Croatian residents bearing this family name were born in Ivanec area and in Zagreb.
Prevalence
About 20 people with faimily name Željko live in Croatia today, in 9 households. There were 100 of them in the middle of the past century, and their number decreased significantly. They are located in four Croatian counties, four cities and two other places, mostly in Karlovac (<10), Ozalj (<5), Zagreb (<5), Sesvete (<5), and in Dramalj (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over ten times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.