Bulgaria, unhappy with its share of riches from the First Balkan War, decided to attack its previous allies, Greece and Serbia. Both countries fight back and eventually enter Bulgaria whose sudden outrage and change of mind angers Romanians who decide to join in on the fighting. While Serbia, Greece, and Romania are busy attacking their former ally, Bulgaria, the Ottoman Empire decides that the Second Balkan war is the perfect time for them to strike back and they regain some of their lost territory. Once the war ended, Bulgaria had to give up some of its earnings from the First Balkan War to Romania, Greece, and Serbia.
Picture: http://klicevac.free.fr/Images/2ndguerrebalkaniquegf.gif