In Croatia, Osojnik families are generally Croats (from Zapresic area ), very rarely Serbs. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Sisak.
Prevalence
About 30 people with faimily name Osojnik live in Croatia today, in 17 households. There were 50 of them in the middle of the past century, and their number decreased by 40 percent. They are located in only four naselja i to in Zagreb (25), Sesvete (<5), Prekvrsje (<5), and in Marija Gorica in Zapresic area (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.