In Croatia, Ostarčević families are almost entirely Croats (from Duga Resa ), barely Serbs. In the past century, relatively most of Croatian residents bearing this family name were born in Karlovac and Duga Resa.
Prevalence
About 40 people with faimily name Ostarčević live in Croatia today, in 18 households. There were 40 of them in the middle of the past century, and their number remains constant. They are located in 6 Croatian counties, in 8 cities, mostly in Duga Resa (15), Karlovac (10), Rijeka (<5), Zagreb (<5), and in Zadar (<5).
Outside Croatia
Family name Ostarčević is present in five countries on four continents. The family name "Ostarcevic " is used by some 50 people in Australia , small number in the United States , and small number of people in France.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1942 in source Phone Directory of the Independent State of Croatia 1942.