Ever wonder how countries end up with the borders they have today? The history of territorial changes is complex but fascinating. Take Bulgaria and Greece, for example. After World War I, the Treaty of Neuilly-sur-Seine redrew parts of their boundary, with land transfers that still impact the region today. If you’ve traveled between these two countries, you’ve likely crossed this border. But a century ago, some of that land belonged to Bulgaria. Through the treaty, Bulgaria lost land to Greece, including the fertile Struma river valley and access to the Aegean Sea. Greece gained valuable territory that strengthened its borders. While the treaty attempted to resolve territorial disputes after the war, its legacy lives on in the political and economic relations between Bulgaria and Greece. If you want to understand modern Balkan politics, delving into this historical treaty is a great place to start.
The Aftermath of World War 1: Setting the Stage for Neuilly
The end of World War 1 in 1918 meant the dissolution of empires and reshaping of national boundaries. Bulgaria had fought on the losing side with the Central Powers, and the price of defeat was dear.
The Treaty of Neuilly, signed in November 1919, forced Bulgaria to give up territory to its neighbors. Greece gained the largest portion, expanding its northern border. This added drama to an already tense relationship between the countries.
Bulgaria lost land it had gained in the 1912-1913 Balkan Wars and its outlet to the Aegean Sea. This gave Greece control of key ports like Kavala that had been in Bulgaria's hands for decades.
Bulgaria's territorial losses reduced the country by about 25% from its size before WW1. Hundreds of thousands of ethnic Bulgarians now found themselves under Greek rule, fueling resentment.
Greece more than doubled in size and population, gaining lands Greeks considered historically theirs. But now they had to govern large minorities of ethnic Bulgarians, Turks, and others within the expanded borders.
The treaty punished Bulgaria for siding with the Central Powers but failed to resolve deeper ethnic and political tensions in the region. This helped set the stage for conflicts in the decades to follow.
The aftermath of WW1 and treaties like Neuilly redrew national boundaries in Europe with what now seems like a lack of foresight into the long-term consequences. While Greece gained territory and access to the sea, the seeds were sown for future unrest in the region.
What Was Decided at the Treaty of Neuilly?
The Treaty of Neuilly officially ended Bulgaria’s role in World War I and redrew its borders. At the treaty talks, Bulgaria’s neighbors took full advantage to gain territory at Bulgaria’s expense.
What exactly did Bulgaria lose? A lot.
Bulgaria ceded land to nearly all of its neighbors, including Greece, Serbia, Romania and the future Yugoslavia. This amounted to about 25% of Bulgaria’s pre-war territory and 33% of its agricultural lands and mineral resources.
The treaty allowed Greece to nearly double in size by gaining Western Thrace and parts of Eastern Macedonia, including the major port city of Kavala. This massive gain fulfilled Greece’s dream of controlling lands it considered historically Greek.
Serbia absorbed much of the Vardar region, giving it access to the Aegean Sea. Romania took the southern Dobruja region. Yugoslavia acquired parts of the Strumica region.
Bulgaria was forbidden from uniting with other territories populated by ethnic Bulgarians. This doomed the hopes of one day forming a unified Bulgarian state.
The Treaty of Neuilly left Bulgaria crippled and reviled. Bulgarians felt betrayed by their allies and robbed of lands they had fought for in the Balkan Wars. The treaty’s harsh terms and vast loss of territory fueled resentment towards its neighbors that shaped regional politics for decades.
While the treaty fulfilled the territorial ambitions of Greece and the other victors, for Bulgaria it marked a national tragedy that contributed to its isolationism in the following decades. For such a small country, Bulgaria lost a great deal at Neuilly, both physically and psychologically. The deep wounds inflicted at Neuilly would take generations to heal.
Bulgaria Loses Land and Gains Debt
The Treaty of Neuilly-sur-Seine officially ended Bulgaria’s participation in World War I, but it came at a heavy cost. Bulgaria lost land to nearly all its neighbors and was saddled with crushing war debt.
Territory losses
As part of the treaty, Bulgaria ceded land to Greece, Serbia, Romania, and the newly formed Kingdom of Yugoslavia. The biggest loser was Greece, which gained Western Thrace and expanded its coastline on the Aegean Sea. Serbia annexed much of the disputed Macedonian region. Romania took southern Dobruja, giving it control of the Danube River mouth. And Yugoslavia gained small parts of eastern Macedonia. All told, Bulgaria lost about 25% of its prewar territory.
War Reparations
To add insult to injury, Bulgaria was required to pay reparations to the Allied powers, especially Greece and Serbia, for damages caused during the war. The total bill came to a whopping £100 million, equivalent to billions of dollars today. This massive debt weighed heavily on Bulgaria for decades and caused economic hardship and hyperinflation. Bulgaria didn’t finish paying off the reparations until the 1940s.
The Treaty of Neuilly was a bitter pill for Bulgaria to swallow. Having sided with the Central Powers in hopes of gaining land, Bulgaria instead emerged from the war in a weaker position. The territorial and economic losses dealt a blow to national pride and prestige. In the decades following, resentment over the treaty contributed to Bulgaria’s strategic shift toward Germany and a desire to regain lost lands. For Greece and Serbia, on the other hand, the treaty was a triumph that expanded their borders at the expense of their historical rival.
Greece Welcomes New Territories
With the Treaty of Neuilly, Greece gained significant territory that had previously belonged to Bulgaria, expanding the country’s borders. For Greece, the additions meant greater access to the Aegean Sea and control of strategic ports and railways.
Western Thrace
One of the biggest territorial gains for Greece was Western Thrace, an area of over 8,500 square miles bordering the Aegean Sea. Western Thrace provided Greece with more coastline, the port city of Alexandroupoli, and control of railway lines connecting Bulgaria and Turkey. The region was also home to a sizable Greek population, so its transfer to Greece was seen as righting the wrongs of the Treaty of Berlin in 1878 which had given the land to Bulgaria.
Other Gains
In addition to Western Thrace, Greece obtained several Aegean islands off the coast of Eastern Thrace, including Samothrace, Imbros, Tenedos, and smaller islets. Greece also annexed the area around the port city of Kavala, which had been part of Ottoman Macedonia. These acquisitions gave Greece dominance over trade and transportation routes in the northern Aegean.
The territorial changes allowed Greece to gain valuable access to the Aegean coastline and take control of strategic transportation infrastructure in the region. With the collapse of the Ottoman Empire, Greece was able to expand into areas with ethnic Greek populations that had been under Ottoman and Bulgarian control for decades. The Treaty of Neuilly marked the realization of Greece's Megali Idea, or “Great Idea,” to establish a state incorporating all ethnic Greeks. For Bulgaria, the loss of lands and access to the Aegean was a bitter pill to swallow after fighting on the side of the Allied powers in World War I. The treaty left lasting resentment towards Greece and shaped Bulgaria’s neutral stance in World War II.
Overall, the Treaty of Neuilly was a major victory for Greece, helping the country gain control of territories considered historically Greek and giving greater access to the Aegean Sea. The territorial adjustments made after World War I would define the borders of Greece and Bulgaria for decades to come.
Long-Term Impacts on Bulgarian-Greek Relations
The Treaty of Neuilly-sur-Seine redrew borders in the Balkans after World War 1, and it came at the expense of Bulgaria. Bulgaria lost territory to Yugoslavia, Romania, Greece and Turkey. The loss of land to Greece in particular caused lasting tensions between the countries that continue today.
Territorial losses
Bulgaria lost the southern Dobrudzha region to Romania, parts of western Thrace to Greece, and a strip of land to Yugoslavia. The Treaty also legitimized Greece’s control over parts of Macedonia. These losses amounted to about 25% of Bulgaria’s pre-war territory and much of its access to the Aegean Sea. Many Bulgarians still resent Greece for acquiring this land.
Population exchanges
The Treaty led to a mass population exchange between Bulgaria and Greece. About 50,000 Bulgarians in Greek Thrace and 90,000 Greeks in Bulgaria were forced to leave their homes. Forced displacement and loss of ancestral lands fueled further bitterness between the ethnic groups.
Ongoing disputes
Bulgaria and Greece have ongoing disputes over territory, ethnicity and identity. Bulgaria claims Greece is oppressing ethnic Bulgarians in Greek Macedonia and Thrace. Greece accuses Bulgaria of irredentism in claiming these lands. The countries also disagree over the ethnic identity of Slavic speakers in Greek Macedonia, with Bulgaria claiming they are Bulgarians.
Some progress
Relations have improved somewhat since the 1990s, but tensions still remain. The countries have increased trade and cooperation, and Bulgaria joined NATO and the EU alongside Greece. But deep-seated grievances over Neuilly continue to strain the relationship, and full reconciliation remains elusive. Overall, the Treaty of Neuilly created wounds between Bulgaria and Greece that have never completely healed.
Conclusion
So there you have it - how the Treaty of Neuilly cost Bulgaria territory and gave Greece control over lands it had long sought. While the treaty aimed to punish Bulgaria for siding with Germany in World War 1, many Bulgarians still resent the losses to this day. The changes have had lasting impacts, with Greeks making up the majority in Western Thrace and Macedonia now firmly under Greek control. Though a century has passed, borders created by treaties like Neuilly continue to shape the region. Next time you're enjoying a glass of ouzo in Thessaloniki or a cold beer in Plovdiv, raise your glass to the politicians who redrew the map and gave us the Balkans we know today.