On this date in 1940, Mussolini gave an ultimatum to Greece: Allow Axis forces to enter Greek territory and occupy certain strategic locations, or else.
That's what an ultimatum is: an “or else.”
And of course, in this case, the “or else” means “we will attack you, we will kill your people and burn your buildings, we will occupy you you, we will take over your country.”
The Greek ruler, Ioannis Metaxas, is widely believed to have answered the ultimatum by simply saying, “No,” but he really said, “Then it is war.” And sure enough, Italian troops attacked just about an hour later. Greek people took to the streets yelling the Greek word for “No!” – which is spelled “ohi” (or "oxi" or “ochi”) in the English alphabet.
During the war, Greece's brave refusal to cooperate with the Axis powers was celebrated in Greece and Cyprus and in Greek communities around the world.
Ohi Day became a public holiday after the war was over. It is commonly celebrated with parades and exhibitions.
Also on this date: