While the refugees in Austria received decent treatment, the Slovene refugees in Italian camps were treated as state enemies, and several thousand died of malnutrition and diseases between 1915 and 1918. Entire areas of the Slovene Littoral were destroyed. The Treaty of Rapallo of 1920 left approximately 327,000 out of the total population of 1.3 million Slovenes in Italy. After the fascists took power in Italy, they were subjected to a policy of violent Fascist Italianization. This caused the mass emigration of Slovenes, especially the middle class, from the Slovene Littoral and Trieste to Yugoslavia and South America. Those who remained organized several connected networks of both passive and armed resistance. The best known was the militant anti-fascist organization TIGR, formed in 1927 to fight Fascist oppression of the Slovene and Croat populations in the Julian March. Kingdom of Serbs, Croats, and Slovenes (later the Kingdom of Yugoslavia) The Slovene People's Party launched a movement for self-determination, demanding the creation of a semi-independent South Slavic state under Habsburg rule. The proposal was picked up by most Slovene parties, and a mass mobilization of Slovene civil society, known as the Declaration Movement, followed. This demand was rejected by the Austrian political elites; but following the dissolution of the Austro-Hungarian Empire in the aftermath of the First World War, the National Council of Slovenes, Croats and Serbs took power in Zagreb on 6 October 1918. On 29 October, independence was declared by a national gathering in Ljubljana, and by the Croatian parliament, declaring the establishment of the new State of Slovenes, Croats, and Serbs. On 1 December 1918, the State of Slovenes, Croats and Serbs merged with Serbia, becoming part of the new Kingdom of Serbs, Croats, and Slovenes; in 1929 it was renamed the Kingdom of Yugoslavia. The main territory of Slovenia, being the most industrialized and westernized compared to other less developed parts of Yugoslavia, became the main centre of industrial production: Compared to Serbia, for example, Slovenian industrial production was four times greater; and it was 22 times greater than in North Macedonia. The interwar period brought further industrialization in Slovenia, with rapid economic growth in the 1920s, followed by a relatively successful economic adjustment to the 1929 economic crisis and Great Depression. Following a plebiscite in October 1920, the Slovene-speaking southern Carinthia was ceded to Austria. With the Treaty of Trianon, on the other hand, the Kingdom of