Was a direct ancestor of yours an Italian citizen living in Istria, Fiume or Dalmatia before those territories passed to Yugoslavia?

This route is tied to territory rather than to the whole of Italy. It covers Istria, Fiume (now Rijeka), Zara (now Zadar), the Dalmatian islands and Zone B of the Free Territory of Trieste — the areas ceded under the Paris Peace Treaty of 1947 and the Treaty of Osimo of 1975. Names and borders both changed, so if the family talks about Austria, Yugoslavia or somewhere near Trieste, it is worth pinning the town down rather than ruling it out.