The collapse of the Habsburg Empire in 1918 led to the founding of new nation states. Southern Carinthia was claimed by both Carinthia and the State of Slovenes, Croats and Serbs. Armed combat followed, along with occupations and persecutions. Security forces arrested four Schiefling locals at the end of April 1919, including the longstanding Mayor Anton Čežar, and held them as hostages. Schiefling was part of the voting district and at the end of May 1919 it fell under the administration of the State of Slovenes, Croats and Serbs. The demarcation line running through the lake impeded the everyday life and mobility of the population greatly. On 10 October 1920, 55% of those entitled to vote in Schiefling elected to remain with Austria; in total it was 59%.
Gendarmerie report, May 3, 1919 (KLA) 
SHS administration base, vlg. Blatnik (SPD)
