In the midst of World War I, the landing of Entente forces in Thessaloniki, Greece, marked a pivotal moment as Allied military powers sought to open a new front against the Central Powers. On October 6, 1915, British and French troops executed a coordinated operation to land in the city strategically located on the Aegean Sea. This initiative aimed to bolster the efforts of the beleaguered Serbian army, which was facing severe pressure from Austro-Hungarian and German forces on its northern border. The operational success was crucial in preventing the total annihilation of Serbian military forces and represented a major Allied commitment to the Balkans.The establishment of this Allied front in Thessaloniki was characterized by complex geopolitical motivations. Greece, at the time, was experiencing political turmoil and internal divisions regarding participation in the war. King Constantine I favored neutrality, while Prime Minister Eleftherios Venizelos supported joining the Allies. The landing of troops in Thessaloniki, therefore, not only aimed to aid the Serbs but also sought to influence Greece’s political alignment toward the Allies, a critical factor in the southeastern European theater of the war.The landing culminated in the formation of the Salonika Front, which allowed Allied forces to conduct operations across Macedonia. The front became a significant theater of war, where combat fluctuated over the following years. While initially successful, it would later lead to a stalemate, requiring extensive resources and manpower from the Allied powers. The landing in Thessaloniki can thus be seen as both a military operation and an attempt to reshuffle the balance of power in the Balkans during one of history's most impactful conflicts.