The establishment of a Balkan Federation has been a recurrent topic among the peoples of the Balkans. The concept of a Balkan federation emerged in the late 19th century among left political forces in the region. The central aim was to establish a new political unity: a common federal republic unifying the Balkan Peninsula on the basis of internationalism, socialism, social solidarity, and economic equality. The underlying vision was that despite differences among the Balkan peoples the historical need for emancipation was a common basis for unification.
This political concept went through three phases in its development. In the first phase the idea was articulated as a response to the collapse of the Ottoman Empire at the beginning of the 20th century. In the second phase, mostly through the interwar period (1919–1936), the idea of the Balkan federation was taken up by the Balkan Communist parties. The third phase is characterized by the clash between the Balkan Communist leaders and Joseph Stalin, the latter of whom opposed the idea during the post-World War II period.
The first inception occurred in Belgrade in 1865 when a number of Balkan intellectuals founded the Democratic Oriental Federation, proposing a federation from the Alps to Cyprus based on political freedom and social equality. They confirmed their adherence to the ideals of French Revolution in the line of Saint-Simon's federalism and in relation to the socialist ideas of Karl Marx or Mikhail Bakunin. Later, in France, a League for the Balkan Confederation, was constituted in 1894, in which Greek, Bulgarian, Serbian, and Romanian socialists participated, supporting Macedonian autonomy inside the general federation of Southeast Europe, as an attempt to deal with the complexity of the Macedonian Question. The next attempt came immediately after the Young Turk Revolution in 1908. The following year, in Salonika, the Socialist Workers Association merged with two Bulgarian socialist groups, and the Socialist Worker's Federation of Ottoman Workers was founded.