In January, after a successful coup by young army officers, the Ottoman Empire decided to continue the war. After a failed Ottoman counter-attack in the Western-Thracian front, Bulgarian forces, with the help of the Serbian Army, managed to conquer Adrianople, while Greek forces managed to take Ioannina after defeating the Ottomans in the battle of Bizani. In the joint Serbian-Montenegrin theater of operation, the Montenegrin army besieged and captured the Shkodra, ending the Ottoman presence in Europe west of the Çatalca line after nearly 500 years. The war ended officially with the Treaty of London on 30(17) May 1913.