The Greco-Turkish War of 1919–1922, an integral and defining conflict often referred to as the Western Front of the broader Turkish War of Independence, unfolded between May 1919 and October 1922. This significant military confrontation pitted Greece against the burgeoning Turkish National Movement, which emerged from the dissolution of the Ottoman Empire following its defeat in World War I. It was a critical period that reshaped the geopolitical landscape of Anatolia and Thrace, ultimately leading to the birth of the modern Republic of Turkey.

The Genesis of Conflict: Ambitions and Aftermath of World War I

The Greek campaign was primarily instigated by the aspirational territorial promises made by the victorious Western Allies, most notably British Prime Minister David Lloyd George. These pledges envisioned substantial territorial gains for Greece at the expense of the defeated Ottoman Empire. This ambition was deeply rooted in Greece's "Megali Idea" (Great Idea), an irredentist concept aiming to incorporate regions with historically significant Greek populations, drawing parallels to Ancient Greece and the Byzantine Empire, which had long held sway over Anatolian lands before their conquest by the Ottomans. Prominent Greek statesman Eleftherios Venizelos actively championed this vision, believing it was an opportune moment to expand Greek influence and territory.

The armed conflict officially commenced with the highly anticipated landing of Greek forces in Smyrna (modern-day İzmir) on 15 May 1919. Smyrna, a vibrant port city with a substantial Greek population and strong economic ties, was symbolically and strategically crucial. Following their landing, Greek forces advanced considerably inland, rapidly gaining control over significant portions of western and northwestern Anatolia. This extensive territory included key cities such as Manisa, Balıkesir, Aydın, Kütahya, Bursa, and Eskişehir, reflecting the initial success and momentum of the Greek offensive.

Turning Points and Turkish Resilience

However, the Greek advance faced its most formidable challenge and was definitively checked by the resilient Turkish forces at the pivotal Battle of Sakarya, fought from August to September 1921. This epic confrontation, occurring near the Sakarya River, marked a crucial turning point in the war, demonstrating the strategic genius of Mustafa Kemal Atatürk and the newfound resolve of the Turkish National Movement's army. It inflicted heavy casualties on the Greek army and halted their march towards Ankara, the provisional capital of the Turkish Grand National Assembly.

The strategic initiative then shifted decisively to the Turkish side. The Greek front ultimately collapsed with the launching of the Turkish Great Offensive (Büyük Taarruz) in August 1922. This massive, coordinated counter-attack, meticulously planned and executed by Mustafa Kemal and his generals, rapidly overwhelmed the exhausted and overstretched Greek lines. The war effectively culminated with the dramatic recapture of Smyrna by Turkish forces on 9 September 1922, followed by the devastating Great Fire of Smyrna, a tragic event that destroyed much of the city and led to immense human suffering and displacement. This marked the definitive end of Greek military aspirations in Anatolia.

The Aftermath: Peace, Borders, and Population Exchange

As a direct consequence of their military defeat, the Greek government was compelled to accept the demands of the victorious Turkish National Movement. This resulted in Greece relinquishing its territorial claims in Western Anatolia and Eastern Thrace and returning to its pre-war borders. This outcome effectively shattered the "Megali Idea" and reshaped the geopolitical map of the region.

The Allied powers, recognizing the new realities on the ground and the strength of the Turkish National Movement, abandoned the highly punitive Treaty of Sèvres (1920), which had initially partitioned large areas of the Ottoman Empire and was never accepted by the Turks. Instead, they convened a new conference to negotiate a revised peace settlement with the representatives of the Turkish National Movement. This led to the signing of the Treaty of Lausanne in July 1923.

Key Outcomes of the Treaty of Lausanne (1923)

• It officially recognized the full independence of the Republic of Turkey.
• It affirmed Turkey's sovereignty over Anatolia, Istanbul, and Eastern Thrace.
• It established the modern borders of Turkey, largely as they are known today.
• It resolved various outstanding issues, including the status of the Turkish Straits, minority rights, and war reparations.

A significant, albeit controversial, provision of the Treaty of Lausanne was the mandatory population exchange agreement between the Greek and Turkish governments. This agreement led to the forced relocation of approximately 1.5 million Orthodox Christians from Turkey to Greece and roughly 500,000 Muslims from Greece to Turkey. This massive demographic engineering, based on religious identity rather than ethnicity, aimed to prevent future ethnic strife but caused immense human suffering, dislocation, and the loss of centuries-old communities, profoundly impacting the social and cultural fabric of both nations. Notably, exceptions were made for the Greek Orthodox population of Istanbul and the Muslim population of Western Thrace.

The First Battle of İnönü: A Pivotal Turkish Victory

The First Battle of İnönü (Turkish: Birinci İnönü Muharebesi) took place between 6 and 11 January 1921 near İnönü in Hüdavendigâr Vilayet (present-day Eskişehir Province, Turkey). This engagement occurred on the western front of the larger Turkish War of Independence and represented a crucial early test for the nascent Turkish regular army.

This battle holds immense historical significance as it was the first major engagement for the Army of the Grand National Assembly, which had been newly established as a standing army (Düzenli Ordu) to replace the earlier, less organized irregular troops (Kuva-yi Milliye). The victory at İnönü, under the command of Colonel İsmet (later İsmet İnönü), significantly boosted the morale of the Turkish National Movement and solidified the authority and legitimacy of the Grand National Assembly in Ankara. It demonstrated that the new regular army was capable of confronting and defeating a well-equipped enemy, marking a critical step in the Turkish struggle for independence and sovereignty.

Frequently Asked Questions About the Greco-Turkish War

When did the Greco-Turkish War take place?

The war took place between May 1919 and October 1922.

What was the main cause of the Greco-Turkish War?

The primary cause was Greece's ambition to expand its territory into Anatolia, supported by certain Western Allies, against the backdrop of the defeated Ottoman Empire and the rise of the Turkish National Movement resisting foreign occupation.

Which major cities did Greek forces capture initially?

Greek forces advanced inland to capture key cities including Manisa, Balıkesir, Aydın, Kütahya, Bursa, and Eskişehir, following their landing in Smyrna (İzmir).

What was the significance of the Battle of Sakarya?

The Battle of Sakarya in 1921 was a critical turning point where the Turkish forces halted the Greek advance, demonstrating their resilience and marking a shift in momentum in the war.

How did the Greco-Turkish War end?

The war effectively ended with the Turkish Great Offensive in August 1922, leading to the collapse of the Greek front, the recapture of Smyrna by Turkish forces, and the subsequent Great Fire of Smyrna.

What were the key outcomes of the Treaty of Lausanne?

The Treaty of Lausanne, signed in 1923, recognized the independence and sovereignty of the Republic of Turkey over Anatolia, Istanbul, and Eastern Thrace, establishing its modern borders. It also mandated a large-scale population exchange between Greece and Turkey.

What was the significance of the First Battle of İnönü?

The First Battle of İnönü (January 1921) was the first significant victory for the newly formed regular army of the Turkish Grand National Assembly, bolstering Turkish morale and validating the efficacy of their organized forces against the Greeks.