In Croatia, Supanz families are Croats (from Sveti Ivan Zelina ). In the past century, relatively most of Croatian residents bearing this family name were born in Sveti Ivan Zelina.
Prevalence
Only a few people with faimily name Supanz live in Croatia today, in one household only. They are located in only one small Croatian place, in Biskupec Zelinski (<5).
Outside Croatia
Family name Supanz is present in 8 countries on three continents. "Suppanz " is used by small number of people in Germany , small number in Austria , and small number of people in the United States.
In the sources analysed in the project Acta Croatica so far, the name is mentioned over five times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.