The Triveneto (triˈvɛːneto) or Tre Venezie (ˈtre vveˈnɛttsje; Tre Venesie; "Three Venetias"; Venetien), also often referred to as North-Eastern Italy or simply North-East (Italia nord-orientale or Nord-Est), is a historical region of Italy. The area is made up of the three smaller historical regions of Venezia Euganea ("Euganean Venetia"), Venezia Giulia ("Julian Venetia") and Venezia Tridentina ("Tridentine Venetia"). This territory was named after the Roman region of Venetia et Histria.
Nowadays the name Triveneto is more commonly used in the Northern Italian languages, while its original title is still in use in the Southern Italian languages, and it includes the three administrative regions of Veneto, Friuli-Venezia Giulia and Trentino-Alto Adige/Südtirol: that is to say, the provinces of Belluno, Bolzano, Gorizia, Padua, Pordenone, Rovigo, Trento, Treviso, Trieste, Udine, Venice, Verona, and Vicenza. This area also corresponds to the Roman Catholic Ecclesiastical Region of Triveneto.
The entire area was under Austrian rule in 1863; Italy annexed Venezia Euganea in 1866, following the Third Italian War of Independence and a controversial plebiscite (see Venetian nationalism); Venezia Giulia and Venezia Tridentina passed under the Italian rule in 1919, following the end of World War I.
After World War II, Italy retained the most part of Tre Venezie, but lost Slovenian and Croatian majority areas of the upper Isonzo valley (together with the eastern part of Gorizia, today called Nova Gorica), the city of Fiume, most part of Carso region and most part of Istria to Yugoslavia. The areas of Trieste (Zone A) and north-west Istria (Zone B) were formed in the Free Territory of Trieste: in 1954, Italy reannexed Zone A, while Zone B was ceded to Yugoslavia.
This territory [specifically Trentino-Alto Adige/Südtirol and Fruli-Venezia Giulia] is known well for its close ties with the German and Slavic worlds.