The gradual disintegration of the vast multinational empires that controlled the Balkans — the Ottoman and Habsburg Empires — since the beginning of the nineteenth century has produced a multiplicity of nationalist rivalries in the region. Competing national groups have sought to fulfill their right to self-determination and to establish their own national states. The Balkan ethnonational groups have striven for their states to include both as many of their ethnic brethren as possible and lands to which they have had historical claims. Due to the high extent of intermingling of populations of different ethnic origins, as well as to a mismatch between historical “rights” and demographic realities, the nationalist aspirations of different groups have frequently clashed. These conflicts have made the Balkans an extremely war-prone region.

A major factor that reduced the frequency of hot regional wars, even if it did not resolve the fundamental state-to-nation problems, was great power intervention. The latter came either in the form of great power cooperation during the nineteenth-century Concert of Europe, or in the form of hegemony of Germany and later the USSR. Conversely, in other periods, great power competition and great power disengagement exacerbated the regional conflicts and exposed the region to the eruption of hot regional wars.

In the first part of the chapter, which focuses on the 1830–1913 period, there will be an investigation of the effects on regional violence of the different types of great power involvement in combination with those of the extent of the state-to-nation imbalance.