In Croatia, Isaić families are Croats (from Pakrac ). In the past century, relatively most of Croatian residents bearing this family name were born in Nova Gradiska and Split.
Prevalence
Only a few people with faimily name Isaić live in Croatia today, in two households only. There were 0 of them in the middle of the past century, and their number remains constant. They are located in two Croatian cities only, in Split (<5) and Pakrac (<5).
Outside Croatia
Family name Isaić (including: Isaic , Isaich and Issaic ) is present in 12 countries on three continents.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 2007 in source Encyclopaedia of Croatian Surnames.