Respuesta :

Nationalism was a powerful force in these countries so each group longed to extend its border

Answer:

It motivated ethnic groups to fight for territory.  

Explanation:

The Balkan peninsula, for centuries, ruled by the Ottoman Empire. By late 1800, the Ottoman Empire began to crumble and became restricted. During this period, Serbia, Montenegro, Greece, and Bulgaria all achieved independence from the Ottoman Empire. Nationalism was a dominant strength in these countries as a strong nationalism began to spring up among the people. In the Balkan region, many of the ethenic people long to fight for expanding their territories.