In Croatia, Tiljak families are almost entirely Croats (from Zupanja area ), very rarely Serbs. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Vinkovci.
Prevalence
About 30 people with faimily name Tiljak live in Croatia today, in 17 households. There were 60 of them in the middle of the past century, and their number halved. They are located in only five Croatian places: in Zagreb (30), Slavonski Brod (<10), Posavski Podgajci in Zupanja area (<10), Luzani in Pleternica area (<5), and in Strmec in Samobor area (<5).
Outside Croatia
Family name Tiljak (including: Telyak , Tilyak and Teliak ) is present in 12 countries on three continents.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.