- 864 - Edict of Pistres of Charles the Bald orders defensive measures against the Vikings
- 1261 - The city of Constantinople is recaptured by Nicaean forces under the command of Michael VIII Palaiologos, thus re-establishing the Byzantine Empire. The Byzantines also succeed in capturing Thessalonica and the rest of the Latin Empire.
- 1722 - Three Years' War begins along Maine and Massachusetts border.
- 1758 - French and Indian War: The island battery at Fortress Louisbourg in Nova Scotia is silenced and all French warships are destroyed or taken.
- 1759 - French and Indian War: In Canada, British forces capture Fort Niagara from French, who subsequently abandon Fort Rouillé.
- 1797 - Horatio Nelson loses more than 300 men and his right arm during the failed conquest attempt of Tenerife Island (Spain).
- 1799 - At Aboukir in Egypt, Napoleon I of France defeats 10,000 Ottomans under Mustafa Pasha.
- 1814 - War of 1812: Battle of Lundy's Lane - Reinforcements arrive near Niagara Falls for General Riall's British and Canadian force, and bloody, all-night battle with Jacob Brown's Americans commences at 18.00; Americans retreat to Fort Erie.
- 1944 - World War II: Operation Spring - One of the bloodiest days for Canadians during the war: 18,444 casualties, including 5,021 killed.