The diploma Upper Soča Valley from the time of Italian occupation until the incorporation to Yugoslavia (1918–1947) discusses the events in the Upper Soča Valley from the end of World War I until the final incorporation of Primorska to Yugoslavia in 1947. The first half of the diploma mostly gathers actions of Italia in the mentioned area, the building of the fortification system and the preparation for World War II. The description of borders in mountain pastures, checkpoints in the mountains and the day-to-day operation of the mountain pastures are discussed in the following chapter. After that I focused on the events in the Valley during World War II, capitulation of Italy and the retreat of their army from the Soča Valley, the arrival of German army forces and the beginning of the national liberation movement in the upper Soča Valley. The second half of the diploma discusses the end of World War II and conditions in the Upper Soča Valley after the war until 1947 when the Primorska region was finally incorporated to Yugoslavia. The division in zone A and B, the Morgan line and life of the people in the Upper Soča Valley during 1945–1947 is discussed in the last chapter of the diploma.