- Signed between Germany and the Allied Powers, this treaty ended World War I and imposed harsh conditions on Germany.
- Germany lost significant territories, including Alsace-Lorraine to France, Eupen-Malmédy to Belgium, North Schleswig to Denmark, and West Prussia, Posen, and Upper Silesia to Poland.
- Germany was restricted in its military capabilities and the size of its armed forces, the Rhineland was demilitarized, and the Allies occupied the Rhineland for 15 years.
- Germany was required to pay reparations to the Allied Powers, the total amount of which would eventually reach 132 billion gold marks (approximately $33 billion).
Treaty of Saint-Germain (1919):
- Signed between Austria and the Allied Powers, this treaty officially dissolved the Austro-Hungarian Empire and established the Republic of Austria.
- Austria lost significant territories, including South Tyrol to Italy, Istria and Dalmatia to the Kingdom of Serbs, Croats, and Slovenes (later Yugoslavia), Bukovina to Romania, and Galicia and Lodomeria to Poland.
- Austria was prohibited from uniting with Germany and had to pay reparations to the Allied Powers.
Treaty of Trianon (1920):
- Signed between Hungary and the Allied Powers, this treaty formalized the breakup of the Austro-Hungarian Empire and defined the borders of Hungary.
- Hungary lost two-thirds of its pre-war territory, with significant areas going to Romania, Czechoslovakia, and the Kingdom of Serbs, Croats, and Slovenes.
- Hungary was banned from forming a customs union with Austria and had to pay reparations to the Allied Powers.
Treaty of Neuilly (1919):
- Signed between Bulgaria and the Allied Powers, this treaty concluded Bulgaria's participation in World War I.
- Bulgaria ceded Western Thrace to Greece and southern Dobruja to Romania, and its access to the Aegean Sea was limited.
- Bulgaria was prohibited from having an air force and had to reduce the size of its military, along with paying reparations to the Allied Powers.
Treaty of Sèvres (1920) (never fully implemented):
- Signed between the Allied Powers and the Ottoman Empire, this treaty aimed to partition the Ottoman Empire and establish new states in the Middle East.
- It allocated significant territories to Greece, Armenia, and an Arab state, effectively dismantling the Ottoman Empire.
- However, the treaty faced strong resistance from the Turkish National Movement, led by Mustafa Kemal Atatürk, and was superseded by the Treaty of Lausanne in 1923.
Treaty of Lausanne (1923):
- Replaced the Treaty of Sèvres and defined the modern borders of Turkey.
- Turkey regained control of Eastern Thrace, Smyrna, and most of Anatolia, while losing territories in the Middle East and North Africa.
- The Ottoman Empire was officially abolished, and the Republic of Turkey was established under the leadership of Mustafa Kemal Atatürk.