In Croatia, Slivnjak families are almost entirely Croats (from Krapina area ), barely Slovenes (from Zagreb ). In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Krapina area.
Prevalence
About 50 people with faimily name Slivnjak live in Croatia today, in 30 households. There were 80 of them in the middle of the past century, and their number decreased by 40 percent. They are located and 5 other Croatian places, mostly in Zagreb (20), in Radoboj (10) and Gornja Semnica (<10) in Krapina area, Belovar (<10), and in Buzin (<5).
Outside Croatia
Family name Slivnjak (including: Slivnyak , Slivniak ) is present in 10 countries on three continents. "Slivnyak " 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 five times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.