In Croatia, Kotrba families are predominantly Croats (from Ilok ), rarely Czechs (from Daruvar area ), and very rarely Slovaks (from Osijek ). In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Ilok.
Prevalence
About 10 people with faimily name Kotrba live in Croatia today, in 6 households. There were 10 of them in the middle of the past century, and their number remains constant. They are only located in four Croatian cities and two other places, mostly in Osijek (<5), Ilok (<5), Zagreb (<5), and in Daruvarski Brestovac (<5) and Dezanovac (<5) in Daruvar area.
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.