Trentino-Alto Adige/Südtirol (US: , UK: ; Italian: Trentino-Alto Adige [trenˈtiːno ˈalto ˈaːdidʒe]; German: Trentino-Südtirol; Ladin: Trentin-Südtirol) is an autonomous region of Italy, located in the northern part of the country. The region has a population of 1.1 million, of whom 62% speak Italian as their mother tongue, 30% speak German dialects and several foreign languages are spoken by immigrant communities. Since the 1970s, most legislative and administrative powers have been transferred to the two self-governing provinces that make up the region: the Province of Trento, commonly known as Trentino, and the Province of Bolzano, commonly known as South Tyrol (Alto Adige in Italian).
From the 9th century until 1801, the region was part of the Holy Roman Empire. After being part of the short-lived Napoleonic Republic of Italy and Napoleonic Kingdom of Italy, the region was part of the Austrian Empire and its successor Austria-Hungary from 1815 until its 1919 transfer to Italy in the Treaty of Saint-Germain-en-Laye at the end of World War I. Together with the Austrian state of Tyrol it is represented by the Euroregion Tyrol-South Tyrol-Trentino.
In English, the region is known as Trentino-South Tyrol or by its Italian name Trentino-Alto Adige.