In Croatia, Jeršić families are Croats (from Krizevci area ). In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Samobor.
Prevalence
About 10 people with faimily name Jeršić live in Croatia today, in five households only. There were 20 of them in the middle of the past century, and their number halved. They are located in two Croatian cities only, in Zagreb (<10) and Rude (<5).
Outside Croatia
Family name Jeršić (including: Jersic , Yersich ) is present in three countries on two continents. "Yersich " is used by few people in the United States.
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.