During the First World War, it carried the majority of Austrian military supplies to the Isonzo Front. Due to new political divisions in Europe, with the dissolution of Austria-Hungary into separate states in 1918 and the isolation of communist Yugoslavia after 1945, the railway decreased in importance during the twentieth century. However, Slovenia's accession to the European Union has created new prospects for the railway as a convenient passenger and freight route from Central and Eastern Europe to the port of Trieste.