11 April

11 April 1034	Byzantine Empire [political events]	When the Byzantine emperor Romanus III dies, he is succeeded by Michael IV the Paphlagonian, who marries Zoe, widow of Romanus and daughter of Constantine VIII.
11 April 1163	Hungary [administration]	With the death of his rival Stephen IV, King Stephen III of Hungary regains full control of his kingdom.
11 April 1167	Kingdom of Jerusalem, Zangid Emirate, Fatimid Caliphate, Egypt [wars]	King Amalric I of Jerusalem, in alliance with the Fatimid vizier Shawar, defeats the Syrians under the Zengid general Shirkuh and his nephew Saladin near Cairo, Egypt. Both the Syrians and the Franks of Jerusalem subsequently agree to leave Egypt.
11 April 1229	France, Toulouse [treaties]	The Treaty of Paris ends the Albigensian Crusade against the Albigensian (Cathar) heretics of Languedoc, southern France; Count Raymond VII of Toulouse submits to King Louis IX of France, ceding the duchy of Narbonne.
11 April 1241	Mongol Empire, Hungary, Croatia, Germany, Holy Roman Empire [Mongol conquests (1206–1405)]	The main Mongol army, under Batu, defeats the Hungarians at Mohi on the River Sajo: they ravage the Danube plain, but are repulsed at Grobnok by the Croatians. A crusade is proclaimed against them in Germany.
11 April 1512	France, Italy, Papal States, Spain [wars]	Este (Ferrarese) artillery and French cavalry under Gaston, comte de Foix, defeat the Spanish and papal forces of the anti-French Holy League in a bitter battle at Ravenna, Italy, but Gaston's death in battle mars French prospects in Italy.
11 April 1514	Rome [births and deaths]	Donato Bramante, Italian chief architect of St Peter's in Rome, who introduced the High Renaissance style, dies in Rome, Italy (c. 70).
11 April 1564	England, France [treaties]	After nine months of issuing empty threats, following the surrender of Le Havre, Queen Elizabeth I of England capitulates to French demands in the Treaty of Troyes; she renounces her claim to Calais for 120,000 crowns.
11 April 1713	France, UK, United Netherlands, Prussia, Portugal, Savoy [War of the Spanish Succession (1701–1714)]	The Peace of Utrecht, the treaty ending the War of the Spanish Succession, is agreed and signed by France, Britain, the United Netherlands, Prussia, Portugal, and Savoy. Philip V, a Bourbon, is recognized as king of Spain, but Spain and France are never to be united under one king. France agrees to dismantle the naval base at Dunkirk, to recognize the Protestant succession in Britain, and to cede Newfoundland, Acadia, and Hudson Bay to Britain, but gains fortresses on the Canadian frontier. Spain cedes San Sacramento north of the River Plate to Portugal and cedes the Spanish Netherlands (now Belgium) to the United Netherlands, to be given to the Holy Roman Emperor once the United Netherlands has established a fortified barrier against French expansion. Sicily is to be united under Savoy as a kingdom. The elector of Brandenburg, in his new capacity as king of Prussia, receives recognition of the royal title and gains Neuchâtel (a canton in Swiss Confederation) and the upper quarter of Gelderland (Guelders), Austrian Netherlands. Prussia's claim upon the principality of Orange, on the River Rhône, is transferred to France.
11 April 1814	France, Italy [Napoleonic Wars (1803–15)]	By the Treaty of Fontainebleau, the French emperor Napoleon I abdicates unconditionally and is banished to the principality of Elba, an island off the west coast of Italy, on an annuity of 2,000,000 francs. Queen Marie-Louise is given the duchies of Gustalla, Parma, and Piacenza.
11 April 1843	Gambia, Sierra Leone, UK [law and government]	A British act of Parliament separates Gambia from Sierra Leone, west Africa, as a crown colony.
11 April 1891	Russia [births and deaths]	Sergey Sergeyevich Prokofiev, Russian composer, born in Sontsovka, Ukraine, Russia (–1953).
11 April 1922	USA [boxing]	A boxing match between the US fighters Johnny (Joe) Dundee and Johnny Ray at Motor Square, Pittsburgh, USA, is the first sporting event to be broadcast on the radio.
11–14 April 1935	Italy, France, UK, Germany [diplomacy]	The prime ministers of Italy, France, and Britain, conferring in Stresa, Italy, protest against German rearmament and agree to act jointly against Germany, forming what becomes known as the Stresa Front.
11–18 April 1944	USSR, Germany [World War II (1939–45)]	Soviet forces clear all of the Crimea, apart from the port of Sevastopol, of German troops.
11 April 1979	Uganda, Tanzania [political events]	The Ugandan capital, Kampala, falls to Tanzanian and rebel forces and the president, Idi Amin, flees the country.
11 April 1987	Italy [births and deaths]	Primo Levi, Italian Jewish writer and chemist who wrote an account of his survival in a Nazi concentration camp, dies in Turin, Italy (67).
11 April 1999	India, Pakistan [weapons]	Indian military forces conduct a test launch of a ballistic missile that is capable of carrying a nuclear warhead. Three days later Pakistan conducts two similar launches, renewing international concerns over the possibility of a nuclear arms race in south Asia.
11–28 April 2006	Iran [diplomacy]	Iranian president Mahmoud Ahmadinejad announces that his country has successfully enriched uranium in defiance of the United Nations Security Council's demands that Iran stop its suspected drive to acquire nuclear weapon technology. Later in the month, the International Atomic Energy Agency confirms Iran's failure to comply with a 30-day deadline set in March to give up its enrichment programme.
11 April 2006	[space exploration]	The Venus Express space probe, the European Space Agency's first exploratory mission to Earth's neighbouring planet, reaches Venus and successfully goes into orbit after a five-month, 248-million mile trip.

April 11

11 April