The Cessation of Bulgarian (or Western) Thrace to Greece

Western Thrace, stretching from the Rhodope Mountains in (mostly) Bulgaria to the Aegean Sea, had already changed hands several times in the early 20th century. The last time Western Thrace was transfered from Bulgaria to Greece was in the aftermath of the First World War.

The Balkan Wars
The Balkan Wars were two conflicts that took place in the Balkan states in 1912 and 1913. In the First Balkan War, the four Balkan states of Greece, Serbia, Montenegro, and Bulgaria declared war upon the Ottoman Empire and defeated it, in the process stripping the Ottomans of their European provinces, leaving only Eastern Thrace under Ottoman control. In the Second Balkan War, Bulgaria stupidly fought against the other four combatants of the first war. It also faced an attack from Romania from the north. The war is seen as a prelude to the First World War.

After the Balkan Wars, the 1913 Treaty of Bucharest assigned Western Thrace to Bulgaria, giving it a coveted outlet to the Aegean.

The First World War, however, dramatically altered Bulgaria’s fortunes. Defeated alongside the other Central Powers, Bulgaria faced harsh terms in the 1919 Treaty of Neuilly‑sur‑Seine. Under Article 48, it was compelled to renounce all rights to Western Thrace. This loss not only stripped Bulgaria of territory but also severed its direct access to the Aegean Sea, obviously a major strategic and economic setback.

Following the treaty, Western Thrace did not immediately pass to Greece but was sort of administered by the French. Their governance aimed to maintain stability among the region’s diverse populations (Turks, Greeks, and Bulgarians) while the Allies deliberated its final status.

But the San Remo Conference had already decided that Western Thrace would be awarded to Greece, and the formal handover was codified in the Treaty of Sèvres on 10 August 1920, in which the Allied Powers recognized Greek sovereignty over Western Thrace. The treaty transferred all rights previously held under the Treaty of Neuilly to Greece, establishing new borders. The treaty guaranteed Bulgaria freedom of transit to the Aegean, acknowledging the economic impact of its territorial loss.

Greek forces peacefully occupied Western Thrace on 23 May 1920, marking the practical completion of the transfer. In the years that followed, Greece integrated the region administratively and demographically, while Bulgaria grappled with the consequences of its diminished regional influence.

[Turkeyfied placenames in Western Thrace]

The Treaty of Lausanne also granted the status of a minority to the Muslims of Western Thrace. A similar status was also granted for the Greek minority in Istanbul. But we all know how that ended: By the Expulsion of Greeks from Istanbul in 1922 and the Turkey's Kristallnacht in 1955.

Tensions around minority rights in the region have continued to resurface, as Turkey constantly tries to throw doubt over the interpretation of the Lausanne framework. As the number of students declined steadily (from ~11,000 in 1960 to ~5,000 in 2017), Greece has closed or merged some schools in Thrace. A measure that resulted in fierce protest by Turkey. Strange, because they did exactly the same in 2011. It remains the poorest part of Greece.