In Croatia, Seko families are almost entirely Croats (from Podgorica, Montenegro ), very rarely Serbs. In the past century, relatively most of Croatian residents bearing this family name were born in Dubrovnik and in Dubrovnik area.
Prevalence
About 30 people with faimily name Seko live in Croatia today, in 12 households. There were 50 of them in the middle of the past century, and their number decreased by 40 percent. They are located in four Croatian counties, four cities and 5 other places, mostly in Zadar (<10), Cilipi in Dubrovnik area (<10), Zagreb (<5), Mokosica (<5), and in Dubrovnik (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1942 in source Phone Directory of the Independent State of Croatia 1942.