Mravinac families are Croats and they are mostly from Otocac. In the past century, relatively most of Croatian residents bearing this family name were born in Otocac and Zagreb. In Sinac in Otocac every thirtieth inhabitant had the family name Mravinac.
Prevalence
About 80 people with faimily name Mravinac live in Croatia today, in 50 households. There were 130 of them in the middle of the past century, and their number decreased by 30 percent. They are located in the most of Croatian counties, in 15 cities and 9 other places, mostly in Zagreb (20), Sinac (15), Vinkovci (10), Bartolovci in Slavonski Brod area (<10), and in Osijek (<10).
Outside Croatia
Family name Mravinac is present in five countries on two continents. The family name "Mravinac " is used by some 50 people in Czech Republic and small number in the United States.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1924 in source Emigration Commission Zagreb.