Why did Nationalist conflict rise in the Balkans?

The Balkan states were fiercely jealous of each other and each hoped to gain more territory at the expense of the others. Matters were further complicated because the Balkans also became the scene of big power rivalry. During this period, there was intense rivalry among the European powers over trade and colonies as well as naval and military might. These rivalries were very evident in the way the Balkan problem unfolded.