| 27 January 1377 | England [law and government] | The ‘bad parliament’ meets in England and reverses the acts of the ‘good parliament’, and grants a poll tax of four shillings on everyone over the age of 14 to fund the continuation of the French wars. |
| 27 January 1571 | Persia [births and deaths] | 'Abbas I the Great, Shah of Persia 1588–1629, who expelled the Ottomans and Uzbekhs from Persia, born (–1629). |
| 27 January 1606 | England [crime and punishment] | The English conspirator Guy Fawkes, a veteran of the Spanish Habsburg Army of Flanders, and his accomplices in the Catholic Gunpowder Plot to blow up King James I and Parliament, are executed for treason in London, England (Guy Fawkes, c. 36). |
| 27 January 1756 | Austria [births and deaths] | Wolfgang Amadeus Mozart, considered one of the world's greatest composers, born in Salzburg, Austria (–1791). |
| 27 January 1832 | England [births and deaths] | Lewis Carroll (pen-name of Charles Lutwidge Dodgson), English novelist who writes Alice's Adventures in Wonderland (1865), born in Daresbury, Cheshire, England (–1898). |
| 27 January 1859 | Prussia [births and deaths] | Kaiser Wilhelm II, German emperor and king of Prussia 1888–1918, born in Potsdam, near Berlin, Prussia (–1941). |
| 27 January 1865 | Spain, Peru [treaties] | A treaty between Spain and Peru recognizes the independence of the former Spanish colony, following ongoing friction since the latter's cession. |
| 27 January 1901 | [births and deaths] | Giuseppe Fortunino Francesco Verdi, Italian operatic composer, dies in Milan, Italy (87). |
| 27 January 1944 | USSR, Germany [World War II (1939–45)] | Soviet forces clear German troops from the Leningrad–Moscow railway line, ending the German siege of Leningrad after 900 days and over 1 million civilian deaths from starvation and enemy action. |
| 27 January 1967 | USA [space exploration] | Three US astronauts, Gus Grissom, Edward White, and Roger B Chaffee, die in a fire during a countdown rehearsal on the Apollo 1 spacecraft at Cape Kennedy, Florida. They are the first human casualties of the US space programme. |
| 27 January 1973 | USA, North Vietnam, South Vietnam, France [Vietnam War (1954–75)] | The USA, North and South Vietnam, and the Vietcong (armed forces of the National Front for the Liberation of South Vietnam) sign a Vietnam War ceasefire agreement in Paris, France. |
| 27 January 1998 | USA [astronomy] | Al Schultz of the Space Science Institute in Baltimore, Maryland, using the Hubble Space Telescope, announces the discovery of a giant planet, larger than the Sun, orbiting Proxima Centauri, the closest star to Earth. It is the first planet outside the Solar System to be directly observed. |
