The name derives from the Vardar River and is primarily associated with the period of Serbian (1912–1918) and later Yugoslav rule (1918–1991).
[4][5] From 1919 to 1922, the area (including parts of today Kosovo and Eastern Serbia) was part of South Serbia (Serbian: Jужна Србија, Južna Srbija),[6][7][8] In 1929, the Kingdom of Yugoslavia was divided into provinces called banovinas.
[9] During World War I it was occupied by Bulgaria as part of the Military Inspection Area of Macedonia.
After the war the present-day Strumica and Novo Selo municipalities were broken away from Bulgaria and ceded to Yugoslavia.
During the Second World War, Bulgaria established two administrative districts in the region – Bitola and Skopje.