Lord Ashcroft David Cameron piggate
Lord Ashcroft has co-authored an embarrassing biography of David Cameron, the Conservative prime minister, called Call Me DaveMatt Cardy/Getty Images

Hell hath no fury like a peer scorned, apparently. Lord Ashcroft, a Conservative and longtime party donor, has unleashed a flurry of scurrilous claims against the prime minister, David Cameron, in a new unauthorised biography about the man, called Call Me Dave.

In it, Ashcroft and co-author Isabel Oakeshott interview dozens of sources who know or have known Cameron in his life. Among the most embarrassing revelations to come to light is a claim that in order to gain entry to the exclusive Piers Gaveston Society dining club at Oxford University, the student Cameron put his penis into the mouth of a dead pig as an initiation. The allegation is made by an anonymous backbench Tory MP, and Cameron is not commenting on it.

So why is Ashcroft, a man who shares a party with Cameron, unleashing such humiliating stories on his political leader? He and Oakeshott say the whole biography is an objective piece of work on Cameron's life and that such stories are just colourful anecdotes. But others are suggesting that it is Ashcroft's revenge for being overlooked by Cameron for a government role because of the scandal around the tax avoiding billionaire's non-dom status.

Maybe it was revenge, maybe not -- but here are some well-known acts of revenge from history.

Et tu, Brute?

Julius Caesar was assassinated by a band of conspirators against his emperorship, among them his friend and protegé Marcus Junius Brutus. Former enemies, Caesar had pardoned Brutus, a staunch republican, and made him a governor.

"Long optimistic about Caesar's plans, Brutus was shocked when, early in 44BCE, Caesar made himself perpetual dictator and was deified," according to the Encyclopedia Britannica. "Always conscious of his descent from Lucius Junius Brutus, who was said to have driven the Etruscan kings from Rome, Brutus joined Cassius and other leading senators in the plot that led to the assassination of Caesar on March 15, 44BCE."

The phrase "Et tu, Brute?" is synonymous with revenge and betrayal because these are the final words attributed to Caesar before his assassination in the Shakespeare play that bears his name.

Boudicca-ming to get you

Boudicca, ancient Briton and queen of the Iceni tribe, unleashed hell on the Roman Empire. When her husband Prasutagus, King of the Iceni, died, she and their two daughters inherited his wealth. Knowing they were living under the imperial thumb of Rome, he also left money to the Emperor Nero, in order to maintain peace with the Empire for his family and their tribe. But the Romans were having none of it and invaded Iceni territory, raping, plundering and pillaging their way through the area, which is modern day East Anglia. So Boudicca raised an army and went marauding against the Romans around ancient Britain, slaughtering 70,000 of them in the process. After the final battle and Roman victory, Boudicca died, perhaps by poisoning herself.

Comrade Stalin salutes you

Leon Trotsky was supposed to succeed Lenin as leader of the Soviet Union, but Stalin seized control instead. Trotsky came from the more democratic -- or shall we say, less totalitarian -- wing of the Communist Party and spoke out against what Stalin was doing after he took power in 1924.

So Stalin being Stalin, he drove Trotsky into exile and tried him in absentia, finding him guilty of trumped up treason charges and a death sentence followed. It wasn't until 1940, when Trotsky was living in Mexico City, that Stalin's revenge was realised when a Spanish assassin working on behalf of the Soviet Union, Ramon Mercader, stuck a pickaxe into Trotsky's head, killing him.

Strike when the Heseltine is right

As defence secretary, Michael Heseltine was a senior member of Margaret Thatcher's cabinet when he stormed out and resigned in a dispute over a deal to save the Westland Helicopters firm, which manufactured choppers. Heseltine wanted it to merge with European firms, Thatcher and others in the cabinet an American one. The row was public and bruising, with allegations and leaks flying left, right and centre. Somehow, Thatcher survived the affair and Heseltine was relegated to the backbenches. Then, in 1990, Heseltine sought his revenge when Thatcher was at her weakest amid another row over Europe -- and he openly challenged her for the leadership. Though she was winning on votes, she stepped down because her leadership had been weakened beyond repair. In stepped John Major and Douglas Hurd. Unfortunately for Heseltine, the sweetness of his revenge against Thatcher soon soured -- he lost to Major in the election.