Jasenko is a male name, in Croatia almost exclusively Croatian. It is one of the relatively common names (among the top two thousand) in Croatia, with over two hundred namesakes living there.
The relative popularity of names Jasenko in Croatia
The name Jasenko was the most popular from years 1973 to 1982. The peak year was 1977.
Prevalence
Name Jasenko is relatively more common in the north of the country. Most of the persons named Jasenko live in the following cities and municipalities: Zagreb (about forty), Karlovac (less than ten), Osijek (less than ten).
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.