Trtanj families are Croats and they are mostly from Senj area. In the past century, relatively most of Croatian residents bearing this family name were born in Sisak and in Senj area.
Prevalence
About 230 people with faimily name Trtanj live in Croatia today, in 100 households. There were 240 of them in the middle of the past century, and their number remains constant. They are located in the most of Croatian counties, in 23 cities and 24 other places, mostly in Sisak (45), Zagreb (40), Krizpolje in Senj area (15), Rijeka (10), and in Osijek (10).
Outside Croatia
Family name Trtanj (including: Tertany , Trtany ) is present in 8 countries on three continents. The family name "Trtanj " is used by small number of people in Germany , small number in the United States , and small number of people in Austria. "Tertany " is used by small number of people in the United States.
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.