April 1 events in history

286 Emperor Diocletian elevates his general Maximian to co-emperor with the rank of Augustus and gives him control over the Western regions of the Roman Empire
325 Crown Prince Jin Chengdi, age 4, succeeds his father Jin Mingdi as emperor of the Eastern Jin Dynasty
457 Majorian is acclaimed emperor by the Roman army
527 Byzantine Emperor Justin I names his nephew Justinian I as co-ruler and successor to the throne
528 The daughter of Emperor Xiaoming of Northern Wei was made the "Emperor" as a male heir of the late emperor by Empress Dowager Hu, deposed and replaced by Yuan Zhao the next day; she was the first female monarch in the History of China, but not widely recognised
1293 Robert Winchelsey leaves England for Rome, to be consecrated as Archbishop of Canterbury
1318 Berwick-upon-Tweed is captured by the Scottish from England
1340 Niels Ebbesen kills Gerhard III of Holstein in his bedroom, ending the 1332-1340 interregnum in Denmark
1545 Potosí is founded after the discovery of major silver deposits in the area
1572 In the Eighty Years' War, the Watergeuzen capture Brielle from the Spaniards, gaining the first foothold on land for what would become the Dutch Republic
1625 A combined Spanish and Portuguese fleet of 52 ships commences the recapture of Bahia from the Dutch during the Dutch–Portuguese War
1789 In New York City, the United States House of Representatives holds its first quorum and elects Frederick Muhlenberg of Pennsylvania as its first House Speaker
1826 Samuel Morey patents the internal combustion engine
1833 The Convention of 1833, a political gathering of settlers in Mexican Texas to help draft a series of petitions to the Mexican government, begins in San Felipe de Austin
1854 Charles Dickens' novel Hard Times begins serialisation in his magazine, Household Words
1865 American Civil War: Battle of Five Forks
1867 Singapore becomes a British crown colony
1871 The first stage of the Brill Tramway opens
1873 The White Star steamer RMS Atlantic sinks off Nova Scotia, killing 547 in the worst marine disaster of the 19th century
1887 Mumbai Fire Brigade is established
1891 The Wrigley Company is founded in Chicago, Illinois
1893 The rank of Chief Petty Officer in the United States Navy is established
1908 The Territorial Force (renamed Territorial Army in 1920) is formed as a volunteer reserve component of the British Army
1918 The Royal Air Force is created by the merger of the Royal Flying Corps and the Royal Naval Air Service
1919 The Staatliches Bauhaus school is founded by Walter Gropius in Weimar
1922 Six Irish Catholic civilians are shot and beaten to death by a gang of policemen in Belfast, Northern Ireland
1924 Adolf Hitler is sentenced to five years in jail for his participation in the "Beer Hall Putsch". However, he spends only nine months in jail, during which he writes Mein Kampf
1924 The Royal Canadian Air Force is formed
1933 The recently elected Nazis under Julius Streicher organize a one-day boycott of all Jewish-owned businesses in Germany, ushering in a series of anti-Semitic acts
1933 English cricketer Wally Hammond sets a record for the highest individual Test innings of 336 not out, during a Test match against New Zealand
1935 India's central banking institution, The Reserve Bank of India is formed
1936 Odisha formerly known as Kalinga or Utkal becomes a state in India
1937 Spanish Civil War: Jaén, Spain is bombed by Nazi forces
1939 Spanish Civil War: Generalísimo Francisco Franco of the Spanish State announces the end of the Spanish Civil War, when the last of the Republican forces surrender
1941 Fântâna Albă massacre: between 200 and 2,000 Romanian civilians are killed by Soviet Border Guards
1941 The Blockade Runner Badge for the German navy is instituted
1941 A military coup in Iraq overthrows the regime of 'Abd al-Ilah and installs Rashid Ali as Prime Minister
1944 Navigation errors lead to an accidental American bombing of the Swiss city of Schaffhausen
1945 World War II: Operation Iceberg – United States troops land on Okinawa in the last major campaign of the war
1946 Aleutian Island earthquake: An 8.6 magnitude earthquake near the Aleutian Islands creates a tsunami that strikes the Hawaiian Islands killing 159, mostly in Hilo
1946 Formation of the Malayan Union
1947 Paul becomes king of Greece, on the death of his childless elder brother, George II
1948 Cold War: Berlin Airlift — Military forces, under direction of the Soviet-controlled government in East Germany, set-up a land blockade of West Berlin
1948 Faroe Islands gain autonomy from Denmark
1949 Chinese Civil War: The Chinese Communist Party holds unsuccessful peace talks with the Nationalist Party in Beijing, after three years of fighting
1949 The Government of Canada repeals Japanese Canadian internment after seven years
1949 The 26 counties of the Irish Free State become Ireland
1954 President Dwight D. Eisenhower authorizes the creation of the United States Air Force Academy in Colorado
1955 The EOKA rebellion against the British Empire begins in Cyprus, with the goal of obtaining the desired unification ("enosis") with Greece
1957 The BBC broadcasts the spaghetti tree hoax on its current affairs programme Panorama