When after World War I the Tyrolean lands up to Brenner Pass fell to the Kingdom of Italy according to the 1915 Treaty of London, the Italian authorities shifted the border northwards and from 1921 the entire Unterland area up to Bronzolo belonged to the Trentino province. The Fascist regime in Italy decided to force the so-called mixed-language regions to be Italianised while German South Tyroleans insisted on the Salorno border (see Bozner Bergsteigerlied).