In Croatia, Mrdjen families are Croats. In the past century, relatively most of Croatian residents bearing this family name were born in Drnis and Zagreb.
Prevalence
About 20 people with faimily name Mrdjen live in Croatia today, in one household only. There were 10 of them in the middle of the past century, and their number doubled. They are located in four Croatian counties and another small place , mostly in Split (<5), Knin (<5), Rijeka (<5), Bjelovar (<5), and in Donji Muc in Sinj area (<5).
Outside Croatia
Family name Mrdjen is present in 12 countries on four continents. The family name "Mrdjen " is used by small number of people in Swaziland , small number in the United States , and small number of people in Australia.
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.