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Following the Peace Treaty signed on February 10, 1947, there were modifications in the Trieste zone: a part of the Territory which was under the Anglo-American control, included Gorizia, was given back to Italy, while almost the whole of Istria, part of the Anglo-American zone, and the cities Fiume and Pola were assigned to Yugoslavia. Furthermore, it was determined that the "Free Territory of Trieste" be divided into an "A zone", which included Trieste and the coastal band situated between Duino and Albaro Vescovà, to be under Anglo-American administration; and "B zone", which included the north-west side of Istria, to be under Yugoslav administration.
Both the administrations used their own stamps. The Anglo-American administration used Italian stamps after applying the overprint "AMG - FTT" (Allied Military Government - Free Territory Trieste). In the "B zone" special stamps made for Trieste were used, as well as Yugoslavian stamps with overprint; all showed the legend or overprint "STT - VUJA" (Free Territory Trieste - Yugoslav Army Military Administration). Since 1952, in the second part of the abbreviation includes "N" ("Popular", referring to the Army).
On October 1954, the "A zone" was made once again part of the Italian territory, while the "B zone" became part of Yugoslavia.
See also: Italy-Trieste
75th Anniversary, UPU
Inside #16: Stamps on Envelopes
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