In Croatia, Derek families are Croats (from Middle Bosnia ). In the past century, relatively most of Croatian residents bearing this family name were born in Middle Bosnia (Sarajevo area).
Prevalence
About 10 people with faimily name Derek live in Croatia today, in one household only. They are located in only two Croatian places: in Zagreb (<5) and Sjeverovac in Hrvatska Kostajnica area (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over five times, the first time 1937 in source Emigration Commission Zagreb.