In Croatia, Sontag families are generally Croats (from North Herzegovina ), very rarely Bosniaks (from Pula area ), and . In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Bosanian Posavina (Derventa area). In Bradina in North Herzegovina every ninth inhabitant had the family name Sontag.
Prevalence
About 20 people with faimily name Sontag live in Croatia today, in 10 households. There were 10 of them in the middle of the past century, and their number doubled. They are only located in four Croatian cities and threee other places, mostly in Zagreb (10), Sesvete (<10), Pula (<5), Karlovac (<5), and in Medulin in Pula area (<5).
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.