Suman families are usually Croats and they are mostly from Knin area , rarely Italians. In the past century, relatively most of Croatian residents bearing this family name were born in Knin area and in Drnis.
Prevalence
About 150 people with faimily name Suman live in Croatia today, in 70 households. There were 120 of them in the middle of the past century, and their number increased by 30 percent. They are located in the most of Croatian counties, in 13 cities and 12 other places, mostly in Zagreb (65), Rijeka (20), Slavonski Brod (15), Vinkovci (10), and in Sesvete (<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.