In Croatia, Trojan families are almost entirely Croats (from Dubrovnik area ), barely Montenegrins (from Sibenik ). In the past century, relatively most of Croatian residents bearing this family name were born in Osijek and Sibenik.
Prevalence
About 50 people with faimily name Trojan live in Croatia today, in 18 households. There were 50 of them in the middle of the past century, and their number remains constant. They are only located in four Croatian cities and threee other places, mostly in Osijek (10), Zagreb (<10), Sibenik (<10), Korcula on the Island of Korcula (<10), and in Plocice in Dubrovnik area (<10).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1906 in source Yearbook and Directory of Literary Society of St. Jerome 1906.