- January 5: The Naval Battle of Lemnos commences during the First Balkan War.
- January 18: The Naval Battle of Lemnos ends in Greek victory.
- January 24: The first ever combat mission involving naval forces or naval aviation in the world! First Lieutenant Mihail Moutousis and Ensign Aristides Moraitinis not only bombarded the Turkish Navy in the Bay of Nagara, they also reported the location of Turkish ships to the commander of the Hellenic Navy located in Moudros, Limnos. The mission took 2 hours 20 minutes, and the distance traveled totaled some 180 kilometers.
- February 20: The Battle of Bizani in the First Balkan War ends in Greek victory. Greek casualties number 812 dead and 1,500 wounded.
- February 26: The Greek Army comes to control all Epirus - including Northern Epirus - during the First Balkan War.
- March 2: The Greek Army liberates Samos.
- March 18: King George I is assassinated in Thessaloniki by Alexandros Schinas.Crown Prince Constantine ascends to the throne.
- March 21: Crown Prince Constantine takes his oath as King of the Hellenes in the Hellenic Parliament.
- April 2: The funeral of the assassinated King George I is held in Athens.
- May 6: Alexander Schinas (assassin of King George I) kills himself by jumping out of a Police Station window.
- May 30: The Treaty of London concludes the First Balkan War.
- June 16: The Second Balkan War breaks out as Bulgaria attacks Serbia and Greece - her allies in the First Balkan War.
- June 21: During the Second Balkan War, the Battle of Kilkis-Lahanas ends in victory for the Greek army.
- June 27: Greek forces liberate Kavala during the Second Balkan War.
- June 28: Greek forces liberate Serres during the Second Balkan War.
- June 30: The first massacre at Doxato takes place during the Second Balkan War, as Bulgarian troops kill 650 inhabitants of this Drama prefecture town before burning it to the ground. A second massacre would take place in the same town, during World War II, on September 29, 1941.
- July 11: Alexandroupolis (then known as Dedeagac) is liberated by Greek forces during the Second Balkan War. The Treaty of Bucharest will return it to Bulgarian control.
- July 14: Komotini is liberated by Greek forces during the Second Balkan War. The Treaty of Bucharest will return it to Bulgarian control.
- July 29: The Battle of Kresna Gorge commences between Greece and Bulgaria during the Second Balkan War.
- July 31: Bulgaria signs an armistice ending hostilities in the Second Balkan War.
- August 9: The Battle of Kresna Gorge is concluded as Bulgaria surrenders during the Second Balkan War.
- August 10: The Treaty of Bucharest is concluded ending the Second Balkan War.
- August 18: Greek forces vacate Thrace in accordance with the terms of the Treaty of Bucharest.
- November 10: The Ottoman government shuts down the operations of seven Greek newspapers.
- December 1: Crete officially becomes part of Greece. King Constantine I and Prime Minister Eleftherios Venizelos preside on an official ceremony of the raising of the Greek flag on Fort of Firkas Bastion.
- December 17: The Florence Protocol is signed which drew the border between Greece and Albania. Northern Epirus is awarded to the newly-created Albanian state. The Great Powers (England, France, Italy, Russia, Germany, Austria-Hungary) set language as the only criteria for their decision.
- January 18: Yiannis Papaioannou, rebetika songwriter.
- March 13: Lambros Konstantaras, actor
- April 20: Mimis Fotopoulos, actor
- May 21: Gina Bachauer, Greek pianist.
- August 2: Seraphim, Archbishop of Athens.
- August 13: Archbishop Makarios III of Cyprus
- October 17: George Polk, US correspondent murdered in Greece
- November 7: Alekos Sakellarios, director, writer, reporter
- Yiannis Vazos, footballer
- February 10: Kostas Tsiklitiras, Olympic Gold Medallist, during the First Balkan War, from meningitis.
- March 18: King George I, King of the Hellenes
- May 6: Alexander Schinas, assassin of King George I