On August 10, 1913, the Bucharest Peace Treaty was concluded between Romania, Serbia, Montenegro and Greece, on the one hand, and Bulgaria, on the other. The document puts an end to the Second Balkan or Inter-Allied War.
Under the pressure of the Romanian troops that reached the vicinity of Sofia, Bulgaria was forced to cede Southern Dobrudja to Romania and give up its claims to Macedonia. According to the treaty, Serbia gets the Vardar, and Greece – The Aegean part of the district. The Pirin area and Western Thrace remain for Bulgaria. She refused to accept these terms as final and during World War I joined the Central Powers to seek revenge against Serbia.
After the signing of the London Peace Treaty on May 17, 1913, relations in the victorious coalition worsened.
The treaty ends the war, but does not eliminate the military situation in the Balkans. The reason is the tension that arose between the main players in the winning coalition.
If a year ago Bulgaria succeeded through diplomacy in creating an effective and successful bloc against the Ottoman Empire, then in the months surrounding the preparation of the peace treaty in London, Sofia fell into international isolation.
According to some historians, King Ferdinand, blinded by military successes, ordered on June 16, 1913, our army to attack the until recently allies Greece and Serbia.
He is impatient to await the arbitration of the Tsar of Russia. The consequences are deplorable for Bulgaria. On June 27, 1913, Romania declared war on Bulgaria and reached Vratsa without almost any resistance. He met the Serbian army at Belogradchik. Vidin is surrounded. The reason is that the main Bulgarian forces are thrown against the Greeks and Serbs.
On July 5, Vasil Radoslavov's government announced that it agreed to cede Southern Dobrudja to Romania and demanded a truce. In response, Romanian Prime Minister Titu Mayorescu extended an invitation to the warring parties for peace talks in Bucharest. Bulgaria responded first and sent its representatives to the Romanian capital on July 13. Three days later, the delegations of the former Bulgarian allies also arrived in Bucharest – Greece, Serbia and Montenegro.
The Bucharest conference starts on July 17. At the time, hostilities continued as Serbia and Greece insisted on negotiating peace terms before the ceasefire. However, the successful resistance of the Bulgarians near the Kresnen Gorge persuaded Greece to a truce (July 18). On July 21, an agreement was reached on the new border between Bulgaria and Romania, but the efforts of Bulgarian diplomats to win Romanian support against Serbs and Greeks remain unsuccessful.
The Bulgarian-Serbian and Bulgarian-Greek border issues have been settled by July 24. Initially, Pašić proposed the Struma river as the border. This proposal was not accepted, but the Bulgarians were forced to give up Shtip, Radovish and Kochani, who ruled until the war. Venizelos claimed the entire Aegean coast up to the village of Makri (a few kilometers west of Dedeagach), but under pressure from the other participants in the conference he reduced his claims. Russia and Austria-Hungary intervened in Bulgaria's favor in the Kavala negotiations, but Venizelos secured the support of two other great European powers – France and Germany. In the end, the Bulgarian delegates conceded Kavala under the threat of Titu Mayorescu that he, as prime minister, would order the Romanian troops to occupy Sofia.