In Croatia, Illeš families are predominantly Croats (from Zagreb ), rarely Hungarians (from Djakovo area ). In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Djakovo area.
Prevalence
About 10 people with faimily name Illeš live in Croatia today, in 9 households. There were 10 of them in the middle of the past century, and their number remains constant. They are located and another small Croatian place , mostly in Zagreb (<10), Osijek (<5), Cakovec (<5), Rijeka (<5), and in Sibenik (<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.