Vardar Macedonia

Vardar Macedonia (Macedonian: Вардарската Македонија, Serbian: Вардарска Македонија / Vardarska Makedonija) is an area in the north of the geographical region of Macedonia, corresponding with the area of today's Republic of Macedonia. It covers an area of 25,713 square kilometres (9,928 sq mi). It usually refers to the part of the Macedonia region attributed to the Kingdom of Serbia by the Treaty of Bucharest in 1913. It is named after the Vardar, the major river in the area.

...
Wikipedia