What happened in Serbia?

If you mean what happened in recent past, here is answer:

It used to be part of SFR Yugoslavia that consisted of 6 republics: Serbia, Croatia, Montenegro, Bosnia and Hercegovina, Slovenia, Macedonia. Different nations, differenta language, religion, culture, tradition mad country fell appart. Unfortunatelly war started first in Slovenia, than in Croatia and Bosnia. All republics separated, only Serbia and Montenegro stud up togather first under name Yugoslavia, than Republic of Serbia and Montenegro. In 1999 NATO bombed Serbia and Montenegro. Bombing started in march and lasted till june. Than Montenegro separated, and at the moment Serbia is fighting for Kosovo, legal part of country that proclamed independence.