Černjul families are almost entirely Croats and they are mostly from Labin area , rarely Italians. In the past century, relatively most of Croatian residents bearing this family name were born in Pula and Labin. In Ružići in Labin area every fourth inhabitant had the family name Černjul.
Prevalence
About 170 people with faimily name Černjul live in Croatia today, in 80 households. There were 200 of them in the middle of the past century, and their number decreased by 20 percent. They are located in four Croatian counties, in 7 cities and 18 other places, mostly in Labin (35), Pula (30), Nedescina in Labin area (25), Kapelica (10), and in Zagreb (10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over five times, the first time 2007 in source Encyclopaedia of Croatian Surnames.