| 27 August 1105 | Kingdom of Jerusalem, Fatimid Caliphate, Palestine [Crusades (1095–1272)] | King Baldwin I of Jerusalem defeats the Fatimids (Shiite Muslims) in the third battle of Ramleh, ending their attempts to reconquer Palestine. |
| 27 August 1427 | Bohemia, England, Holy Roman Empire [wars] | A crusading army led by the English cardinal Henry Beaufort flees from Stribo on the approach of the Bohemians: the fourth anti-Hussite crusade fails. |
| 27 August 1529 | England, France, Holy Roman Empire [treaties] | King Henry VIII of England accedes to the Treaty of Cambrai of 3 August, making peace with the Habsburgs and recognizing the failure of the foreign policy of his Lord Chancellor, Cardinal Thomas Wolsey. |
| 27 August 1701 | UK, United Netherlands, Austria, Habsburg Monarchy, Holy Roman Empire [War of the Spanish Succession (1701–1714)] | The Treaty of The Hague is signed between Britain, the United Netherlands, and Austria, creating the ‘Grand Alliance’ of the three chief partners in the anti-French coalition in the War of the Spanish Succession. |
| 27 August 1770 | Germany [births and deaths] | Georg Wilhelm Friedrich Hegel, German philosopher of the idealist school, born in Stuttgart, Germany (–1831). |
| 27 August 1828 | Uruguay, Brazil, Argentina [decolonization] | Uruguay is formally proclaimed independent at the preliminary peace ending the war between Brazil and Argentina. |
| 27 August 1882 | USA, Poland [births and deaths] | Samuel Goldwyn, US pioneer Hollywood film-maker and producer, one of the founders of Metro-Goldwyn-Mayer (MGM), born in Warsaw, Poland (–1974). |
| 27 August 1891 | France, Russian Empire [treaties] | A Franco-Russian entente is made as a result of friendlier relations following the break between Germany and Russia. |
| 27 August 1894 | USA [taxation] | The Wilson–Gorman Tariff Act, introducing a 2% income tax, becomes law in the USA, passed by Congress without receiving the assent of US president Grover Cleveland. It is the nation's first graduated income tax. |
| 27 August 1908 | [births and deaths] | Lyndon Baines Johnson, 36th president of the USA 1963–69, a Democrat, born in Gillespie County, Texas (–1973). |
| 27 August 1910 | [births and deaths] | Mother Teresa (born Agnes Gonxha Bojaxhiu), Albanian-born Indian ascetic who founded the Order of the Missionaries of Charity, devoted to helping the poor, born in Yugoslavia of Albanian parents (–1997). |
| 27 August 1916 | Romania, Austria-Hungary [World War I (1914–18)] | Romania joins the Allies and declares war on Austria-Hungary. |
| 27 August 1928 | France, USA, United Kingdom, Germany, France, Italy, Belgium [political events] | The Kellogg–Briand Pact (drawn up by the US secretary of state F B Kellogg and the French foreign minister Aristide Briand), outlawing war and providing for the pacific settlement of disputes, is signed in Paris, France, by 15 states, including the USA. |
| 27 August 1939 | Germany [aircraft] | The Heinkel He 178 makes a test flight in Germany, achieving a speed of 500 kph/360 mph; it is the first jet aeroplane to fly. |
| 27 August 1992 | USA, UK, France, Iraq [wars] | The USA, Britain, and France impose an air exclusion zone in southern Iraq to protect Shiite Muslims from air attacks by the forces of the Iraqi president Saddam Hussein. |
| 27 August 1998 | Russia [economic conditions] | The Russian government's decision to stop propping up the ailing rouble leads to uncertainty about the future of President Boris Yeltsin and the entire reform process, causing global stock markets to plummet. |
