Tadej families are Croats and they are mostly from Kraljevica area. In the past century, relatively most of Croatian residents bearing this family name were born in Rijeka and Bakar. In Benkovac Fužinski in Kraljevica area every fourth inhabitant had the family name Tadej.
Prevalence
About 150 people with faimily name Tadej live in Croatia today, in 70 households. There were 140 of them in the middle of the past century, and their number increased by 0 percent. They are located in 9 Croatian counties, in 14 cities and 20 other places, mostly in Rijeka (35), Zagreb (30), Hreljin (25), Jablan (15), and in Fuzine in Kraljevica area (10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over ten times, the first time 1906 in source Yearbook and Directory of Literary Society of St. Jerome 1906.