Why has it been so difficult to achieve peace and stability in the Balkans?

This region was also politically unstable as there were different ethnicities and there was also rising nationalism in the region. Nationalism brought about tensions. There was also rising Serbian nationalist groups. Combined with the brinkmanship of the European Powers the area became a fuse to the powder keg that Europe had become. The Balkans has strong Cultural, Religious, and language ties to the surrounding Empires but they were in small pockets making nation building difficult.

Louis xvi wanted to force aristocrats to pay taxes for the first time