639 – Ashina Jiesheshuai and his tribesmen assaulted Tai zong at Jiucheng Palace.
715 – Pope Gregory II is elected.
1051 – Henry I of France is married to Anne of Kiev.
1445 – John II of Castile defeats the Infantes of Aragon at the First Battle of Olmedo.
1499 – Catherine of Aragon is married by proxy to Arthur, Prince of Wales. Catherine is 13 and Arthur is 12.
1535 – French explorer Jacques Cartier sets sail on his second voyage to North America with three ships, 110 men, and Chief Donnacona's two sons (whom Cartier had kidnapped during his first voyage).
1536 – Anne Boleyn, the second wife of Henry VIII of England, is beheaded for adultery, treason, and incest.
1542 – The Prome Kingdom falls to the Taungoo Dynasty in present-day Burma.
1568 – Queen Elizabeth I of England orders the arrest of Mary, Queen of Scots.
1643 – Thirty Years' War: French forces under the duc d'Enghien decisively defeat Spanish forces at the Battle of Rocroi, marking the symbolic end of Spain as a dominant land power.
1649 – An Act of Parliament declaring England a Commonwealth is passed by the Long Parliament. England would be a republic for the next eleven years.
1655 – The Invasion of Jamaica begins during the Anglo-Spanish War.
1743 – Jean-Pierre Christin developed the centigrade temperature scale.
1749 – King George II of Great Britain grants the Ohio Company a charter of land around the forks of the Ohio River.
1776 – American Revolutionary War: A Continental Army garrison surrenders in the Battle of The Cedars.
1780 – New England's Dark Day: A combination of thick smoke and heavy cloud cover causes complete darkness to fall on Eastern Canada and the New England area of the United States at 10:30 A.M.
1802 – Napoleon Bonaparte founds the Legion of Honour.
1828 – U.S. President John Quincy Adams signs the Tariff of 1828 into law, protecting wool manufacturers in the United States.
1845 – Captain Sir John Franklin and his ill-fated Arctic expedition depart from Greenhithe, England.
1848 – Mexican–American War: Mexico ratifies the Treaty of Guadalupe Hidalgo thus ending the war and ceding California, Nevada, Utah and parts of four other modern-day U.S. states to the United States for US$15 million.
1897 – Oscar Wilde is released from Reading Gaol.
1911 – Parks Canada, the world's first national park service, is established as the Dominion Parks Branch under the Department of the Interior.
1917 – the Norwegian football club Rosenborg BK was founded.
1919 – Mustafa Kemal Atatürk lands at Samsun on the Anatolian Black Sea coast, initiating what is later termed the Turkish War of Independence.
1921 – The United States Congress passes, and President Warren G. Harding signs, the Emergency Quota Act establishing national quotas on immigration.
1922 – The Young Pioneer Organization of the Soviet Union is established.
1934 – Zveno and the Bulgarian Army engineer a coup d'état and install Kimon Georgiev as the new Prime Minister of Bulgaria.
1941 – The Viet Minh, a communist coalition, formed at Cao Bằng Province, Vietnam.
1942 – World War II: In the aftermath of the Battle of the Coral Sea, Task Force 16 heads to Pearl Harbor.
1943 – World War II: British Prime Minister Winston Churchill and U.S. President Franklin D. Roosevelt set Monday, May 1, 1944 as the date for the Normandy landings ("D-Day"). It would later be delayed over a month due to bad weather.
1943 – World War II: British Prime Minister Winston Churchill pledged his country’s full support of the U.S. in the fight against Japan.
1950 – A barge containing munitions destined for Pakistan explodes in the harbor at South Amboy, New Jersey, devastating the city.
1950 – Egypt announces that the Suez Canal is closed to Israeli ships and commerce.
1959 – The North Vietnamese Army establishes Group 559, whose responsibility is to determine how to maintain supply lines to South Vietnam; the resulting route is the Ho Chi Minh trail.
1961 – Venera program: Venera 1 becomes the first man-made object to fly-by another planet by passing Venus (the probe had lost contact with Earth a month earlier and did not send back any data).
1961 – At Silchar Railway Station, Assam, 11 Bengalis die when police open fire on protesters demanding state recognition of Bengali language in the Bengali Language Movement.
1962 – A birthday salute to U.S. President John F. Kennedy takes place at Madison Square Garden, New York City. The highlight is Marilyn Monroe's rendition of "Happy Birthday".
1963 – The New York Post Sunday Magazine publishes Dr. Martin Luther King, Jr.'s Letter from Birmingham Jail, drafted shortly after his arrest on April 12 during the Birmingham campaign advocating for civil rights and an end to segregation in Birmingham, Alabama. The letter was in response to "A Call for Unity": A statement made by eight white Alabama clergymen against King and his methods, following his arrest, and became one of the most-anthologized statements of the African-American Civil Rights Movement.
1971 – Mars probe program: Mars 2 is launched by the Soviet Union.
1973 – Secretariat wins the Preakness Stakes, the second of his Triple Crown victories.
1986 – The Firearm Owners Protection Act is signed into law by U.S. President Ronald Reagan.
1991 – Croatians vote for independence in a referendum.
1997 – The Sierra Gorda biosphere, the most ecologically diverse region in Mexico, is established as a result of grassroots efforts.
2007 – President of Romania Traian Băsescu survives an impeachment referendum and returns to office from suspension.
2010 – The Royal Thai Armed Forces concludes its crackdown on protests by forcing the surrender of United Front for Democracy Against Dictatorship leaders.
2012 – Three gas cylinder bombs explode in front of a vocational school in the Italian city of Brindisi, killing 1 and injuring 5 others.
2012 – A car bomb explodes near a military complex in the Syrian city of Deir ez-Zor, killing 9 people.
2015 – The Refugio oil spill deposited 142,800 U.S. gallons (3,400 barrels) of crude oil onto an area in California considered one of the most biologically diverse coastlines of the west coast.
Ivo of Kermartin
Joaquina Vedruna de Mas
Maria Bernarda Bütler
Martyr Philoterus of Nicomedia (303)
Martyr Acoluthus of the Thebaid (303)
Martyr Cyriaca (Kyriake) and the six holy virgin-martyrs in Nicomedia (307)
Martyr Theotima of Nicomedia (c. 311)
Hieromartyrs Patricius of Prussa, Bishop, and with him the Presbyters Acacius,
Menander, and Polyainos (362)
Saint John, Bishop of the Goths in Crimea (787)
Virgin-Martyr Pudentiana (Potentiana), daughter of Saint Pudens the senator (160)
Saint Cyril of Trier, Bishop of Trier, (5th c.)
Saint Adolphus (Hadulf), ascetic of the Benedictine Abbey of St. Vaast, in Arras,
and later Bishop of Arras Cambrai in the north of France (728)
Saint Dunstan, Archbishop of Canterbury (988)
who suffered under the Latins (1231):
Barnabas, Gennadius, Gerasimus, Germanus (Herman), Theognostus,
Theoctistus, Jeremiah, John, Joseph, Conon, Cyril, Maximus and Mark
Right-Believing Great Prince Dmitry Donskoy, Great Prince of Moscow (1389)
Venerable Sinaites of Serbia (from Ravanica) (14th century):
Romulus, Romanus, Nestor, Sisoes, Zosimas, Gregory, Nicodemus, and Cyril,
the Sinaites. - disciples of Gregory of Sinai (Mount Athos)
Saint Cornelius of Paleostrov, Abbot (1420)
Saint John (Ignatius), Prince of Uglich, tonsured as Ignatius in Vologda (1522)
Venerable Cornelius of Komel (Vologda), Abbot and Wonderworker (1537)
Saint Sergius of Shukhtov (Shukhtom), monk (1609)
Hieromartyr Innocent (Letayev), Archbishop of Kharkiv (1937)
Hieromartyr Victor Karakulin (1937)
Hieromartyr Onuphrius (Gagaliuk), Archbishop of Kursk and Oboyansk (1938), and:
Hieromartyr: Anthony, Bishop of Belgorod;
Hieromartyrs: Mitrophanes Vilgelmsky, Alexander Yeroshov, Michael Deineka,
Hippolytus Krasnovsky, Nicholas Kulakov, Basil Ivanov, Nicholas Sadovsky,
Maximus Bogdanov, Alexander Saulsky, Paul Bryantsev, and Paul Popov - Priests;
Martyrs: Michael (Voznesensky) and Gregory (Bogoyavlensky) (1938)
New Hieromartyr Valentine Lukyanov (1940)
All New Hieromartyrs of Slobozhanschyna (Slobodskaya) Ukraine (1937,1938,1940,1941)
Translation of the sacred relics of Saints Julius the Presbyter (401)
and Julianus (Giuliano) the Deacon (391)
Repose of Schemamonk Cyriacus of Valaam (1798)
Repose of Righteous Nicholas Rynin of Vologda (1837)
Commemoration of the ascetics of St. Anthony of Syadem Monastery:
Elias (also of Valaam), Theophanes, and Dionysius
Synaxis of Hieromartyrs of Kharkov
Slaying of Priest John Karastamatis of Santa Cruz, martyred by Satanists (1985)