Rumac families are Croats and they are mostly from Buzet area. In the past century, relatively most of Croatian residents bearing this family name were born in Rijeka and Opatija. In Brest Pod Učkom in Buzet area every fifth inhabitant had the family name Rumac.
Prevalence
About 130 people with faimily name Rumac live in Croatia today, in 60 households. There were 160 of them in the middle of the past century, and their number decreased by 20 percent. They are only located in in 11 Croatian cities and 18 other places, mostly in Rijeka (15), Pula (15), Opatija (10), Poljane (<10), and in Zagreb (<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.