Bruce Gudmundsson outlines the operations of Ottoman Empire forces defending “Turkey in Europe” against Greek and Bulgarian invasion (in alliance with Serbia and Montenegro) in 1913:
In the English speaking world, the name Gallipoli invariably evokes memories of the great events of 1915 and 1916. A location of such strategic importance, however, rarely serves as the site of a single battles. Two years before the landings of the British, Indian, Australian, and New Zealand troops on the south-west portion of the the peninsula (and the concurrent French landings on the nearby mainland of Asia Minor near the ruins of the ancient city of Troy), Ottoman soldiers defended the Dardanelles against the forces of the Balkan League.
By the end of January of 1913, the combined efforts of Greece, Serbia, Montenegro, and Bulgaria had driven Ottoman forces from most of “Turkey in Europe”. Indeed, the only intact Ottoman formations on European soil were those trapped in the fortress of Adrianople, those holding the fortified line just west of Constantinople, and those that had recently arrived at Gallipoli.
Soon after arriving, the Ottoman forces on Gallipoli began to build a belt of field fortifications across the narrowest part of the peninsula, a line some five kilometers (three miles) west of the the town of Bolayir. At the same time, they occupied outposts some twenty kilometers east of the line, at the place where the peninsula connected to the mainland.
The general situation in (and around) the Gallipoli Peninsula, 31 January 1913.
On 4 February 1913, the Bulgarians attacked. On the first day of this attack, they drove in the Ottoman outposts. On the second day, they broke through a hastily erected line of resistance, thereby convincing the Ottoman forces in front of them to evacuate Bolayir. However, rather than taking the town, or otherwise attempting to exploit their victory, they withdrew to positions some ten kilometers (six miles) east of the Ottoman earthworks.
While the Ottoman land forces returned to the earthworks along the neck of the Peninsula, ships of the Ottoman Navy operating in the Sea of Marmora located, and began to bombard, the Bulgarian forces near the coast. This caused the Bulgarians to move inland, where they took up, and improved, new positions on the rear slopes of nearby hills.
On 9 February, the Ottomans launched a double attack. While the main body of the Ottoman garrison of Gallipoli advanced overland, a smaller force, supported by the fire of Ottoman warships, landed on the far side of the Bulgarian position. Notwithstanding the advantages, both numerical and geometric, enjoyed by the Ottoman attackers, this pincer action failed to destroy the Bulgarian force. Indeed, in the course of two failed attacks, the Ottomans suffered some ten thousand casualties.
Though the Ottoman maneuver failed to dislodge the Bulgarians from their trenches, the two-sided attack convinced the Bulgarian commander to seek ground that was, at once, both easier to defend against terrestrial attack and less vulnerable to naval gunfire. He found this on the east bank of a river, thirteen kilometers (eight miles) northeast of Bolayir and ten kilometers (six miles) north of the place where the Ottoman landing had taken place.
