- July 4 -
- 323 - Battle of Adrianople Constantine the Great defeats Licinius, who flees to Byzantium
- March 25 -
- 1821 - Greece declares its liberation from the Ottoman Empire, beginning the Greek War of Independence.
- October 28 -
- 1940 - WWII: Italian troops invaded Greece meeting strong resistance from Greek troops and civilians. This action signals the beginning of the Balkans Campaign.
- July 20 -
- 1974 - Invasion of Cyprus In the first of a two stage invasion, Turkish forces land in Kyrenia after Greek Cypriots' attempt at enosis. The northern part of the island is still under occupation to this day.