Bret Cahill thinks conspiracies can only be successful if it is only ONE person who is in on the conspiracy..
Well.... here are a few....
1552 BCE - Apophis Kush Alliance against Egypt as attested to in the second Kamose stele
1st century BCE - Catiline conspiracies
44 BCE - Liberatores conspire to assassinate Julius Caesar to restore Roman Republic. Caesar stabbed to death by group of Senators led by Gaius Cassius Longinus, Marcus Junius Brutus, and Decimus Junius Brutus.
65 CE - Pisonian conspiracy
Late 15th century (1478) Pazzi conspiracy, which included the Pope
1506 - Conspiracy against the life of the brothers Alfonso I d'Este, Duke of Ferrara and Cardinal Ippolito d'Este, coordinated by their half brother Giulio d'Este and full brother Ferrante d'Este
1570 - Ridolfi plot against Elizabeth I of England
1583 - Throckmorton Plot to murder Elizabeth and replace her with her cousin Mary, Queen of Scots
1586 - Babington Plot, second major plot against Elizabeth, that led most directly to execution of Mary, Queen of Scots
1603 - Main Plot to remove James I of England and enthrone Arbella Stuart
— Bye Plot, leads to the execution of Sir George Brooke
1605 - Gunpowder Plot to blow up the House of Lords during the State Opening of Parliament as prelude to a popular revolt in the Midlands, during which James's nine-year-old daughter, Princess Elizabeth, was to be installed as the Catholic head of state; often called the Gunpowder Treason Plot; origin of Guy Fawkes Day
1749 - Conspiracy of the Slaves, ... by Muslim slaves to kill Grand Master Manuel Pinto da Fonseca and take over Malta with the help of the Barbary states.
1788 - Anjala conspiracy
1832 - Georgian plot, assassination of the Russian imperial administration and restoration of the Georgian monarchy
1865 - Abraham Lincoln assassination plot, to include assassination of cabinet members
1898 - The Dreyfus Affair, a coordinated attempt to falsely accuse Alfred Dreyfus of treason
1903 - The Protocols of the Elders of Zion, presented as authentic text by the Tsar's secret police efforts to foment anti-Semitism
1914 - The Black Hand, a secret society controlled by Serbian Military Intelligence, coordinates the assassination of Franz Ferdinand, thus causing World War I.
1917 - 1991 Conspiracy to spread communism in the world. Following World War II by using the "Peace & Dis-armament Movement" in the west.. run by Soviet front organization "World Peace Council".
1924 - The Zinoviev letter, published in the United Kingdom before the 1924 general election, is a letter now believed to be a forgery. It was signed with the name of Grigory Zinoviev and addressed to the Communist Party of Great Britain. Its publication and contents led to speculation of a Russian communist conspiracy. The Conservative Party landslide at the election was partly attributed to the letter.
1938 - Presumed Hitler Youth Conspiracy, NKVD case in Moscow involving some 70 arrests and 40 executions of teenagers and adults, later found to be baseless
1939 - Operation Himmler and its Gleiwitz incident, "False Flag" terrorism by Nazi Germany as pretext for invasion of Poland
— Shelling of Mainila, "False Flag" terrorism by USSR as pretext for Winter War
1943 - Bomb on Hitler's aircraft, an attempt on Adolf Hitler
1944 - July 20 Plot, attempt to assassinate Hitler with suitcase bomb, and then use Operation Valkyrie to grab power
1953 - 1953 Iranian coup d'état Anglo-American conspiracy under the names of 'Operation Ajax' (CIA ) and 'Operation Boot' (MI6)
1954 - Lavon affair Operation Susannah, "False Flag" terrorism by Mossad
1968 - The Markovic affair, French Secret Service Gaullist plot destabilise future president Georges Pompidou
1969 to 1972 Secret war in Laos, and Operation Menu in Cambodia, concealed from Congressional oversight
1972 - Watergate scandal, burglary and cover-up scandals
1982 - Fighting Solidarity
1984 - Brighton hotel bombing - attempted assassination of Margaret Thatcher and her cabinet by the Provisional IRA
1984 Rajneeshee bioterror attack
1987 - Iran-Contra Affair
1991 - Nayirah testimony to rally U.S. public support to launch the Gulf War
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