| 19–29 April 1213 | Italy, Palestine, France [Crusades (1095–1272)] | Pope Innocent III proclaims the Fifth Crusade and stops granting indulgences for the Albigensian Crusade against the Albigensian (Cathar) heretics of southern France. |
| 19 April 1451 | India [administration] | Buhlul Khan, Afghan governor of Punjab, deposes and retires the last Sayyid (claiming descent from Mohammed's grandson Husein) sultan of Delhi, 'Alam Shah, and claims the throne for himself, founding the Lodi dynasty. |
| 19 April 1529 | Holy Roman Empire [political events] | Archduke Ferdinand I of Austria coerces another Diet (legislative assembly) of Speyer into voting to enforce the 1521 Edict of Worms, revoking the Speyer concessions of 1526; the minority – John, Elector of Saxony, George, Margrave of Brandenburg-Ansbach, Philip, Landgrave of Hesse, the princes of Brunswick-Lüneburg and Anhalt, and Nuremberg, Strassburg, and 12 other imperial cities – read their ‘Protest’ against this, giving rise to the term ‘Protestant’. |
| 19 April 1661 | UK [postal services] | The English General Post Office introduces postmarks. |
| 19 April 1666 | UK, France, United Netherlands [treaties] | Britain's sole ally in the war against the Dutch and French, the bishop of Münster in the Holy Roman Empire, sues for peace and a treaty is signed providing for a virtual total disarmament of his forces. |
| 19 April 1775 | America [American Revolution] | Military action in the American Revolution begins with the skirmishes between colonials and British forces under Lieutenant Colonel Francis Smith at Lexington and Concord, Massachusetts; the British force withdraws to Boston. |
| 19 April 1810 | Venezuela, Spain [political events] | Under the influence of the South American nationalist Simón Bolívar, the Junta in Venezuela breaks away from Napoleonic Spain, refusing to recognize Joseph Bonaparte and proclaiming allegiance to Ferdinand VII, the hereditary king of Spain. |
| 19 April 1824 | Greece, England [births and deaths] | George Gordon, Lord Byron, English Romantic poet, dies in Missolonghi, Greece (36). |
| 19 April 1839 | Belgium, Netherlands, Luxembourg [treaties] | The Treaty of London is signed, agreeing the territorial arrangements for the separation of Belgium and the Netherlands. Luxembourg, disputed between the two, becomes an independent grand duchy, and the River Scheldt is opened to the ships of both the Netherlands and Belgium. |
| 19 April 1881 | England [births and deaths] | Benjamin Disraeli, Earl of Beaconsfield, British prime minister 1868 and 1874–80, a Conservative, dies in London, England (76). |
| 19 April 1882 | England [births and deaths] | Charles Robert Darwin, English naturalist who developed the theory of evolution through natural selection, dies in Downe, Kent, England (73). |
| 19 April 1956 | USA, Monaco [cinema and film] | The US film star Grace Kelly marries Prince Rainier of Monaco. The screening of her films in Monaco is subsequently banned. |
| 19 April 1970 | Laos, Cambodia [wars] | The communist Pathet Lao of Laos advances on the Cambodian capital, Phnom Penh, and, on 20 April, the Cambodian government appeals for US assistance. |
| 19 April 1971 | USSR [space exploration] | The USSR launches the 15-m/50-ftlong Salyut 1 space station. Visited by a three-person crew from 7 to 29 June, the cosmonauts die during their return to Earth when a faulty valve causes their capsule to lose pressure. The station re-enters the Earth's atmosphere six months later. |
| 19 April 1971 | Sierra Leone [colonies and mandate] | Sierra Leone becomes a republic within the Commonwealth. |
| 19 April 1993 | USA [political events] | The US Federal Bureau of Investigation (FBI) storms the compound of the Branch Davidian cult in Waco, Texas (under siege since 28 February); over 80 people die when cult members set fire to the compound. |
| 19 April 1998 | USA, UK [births and deaths] | Linda McCartney, US-born British businesswoman and photographer, dies of cancer, near Tucson, Arizona (56). |
| 19 April 2001 | South Africa [medicine] | A group of 39 multinational pharmaceutical firms abandon their court action against South Africa's government over the provision of generic drugs to combat AIDS. |
| 19 April 2005 | Vatican [Catholicism] | The conclave of Roman Catholic cardinals elects Joseph Ratzinger, an orthodox conservative theologian, as the new Pope in succession to the deceased John Paul II. The German-born cardinal adopts the title of Benedict XVI. |
