Mržljak families are Croats and they are mostly from Duga Resa area. In the past century, relatively most of Croatian residents bearing this family name were born in Karlovac and in Duga Resa area.
Prevalence
About 80 people with faimily name Mržljak live in Croatia today, in 30 households. There were 60 of them in the middle of the past century, and their number increased by 40 percent. They are located in 7 Croatian counties, in 8 cities and 10 other places, mostly in Duga Resa (15), Jarce Polje in Duga Resa area (15), Pribanjci in Vrbovsko area (<10), Karlovac (<10), and in Mracin in Duga Resa area (<10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over twenty times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.