To be fair to everybody involved in this, we're not entirely sure that this was a case of blackmail. It gets complicated, so here's a brief summary: a letter was written to England's King Edward III by a Genoese priest in 1337, telling him that his father Edward II hadn't been murdered a decade earlier — rather, he had escaped and was living in Europe. Where does the blackmail part come in? Well, it's pretty much assumed Edward III had ordered his dad's death, so his being alive and revealing his escape would hardly be convenient.

The fact that the priest later became a bishop and received several appointments from Edward III has led a few historians to wonder if the letter was blackmail, designed to threaten the king's reputation and get him to pay some debts to the priest's notable family, the Fiescis. We're not sure if these allegations are true, though, and the historian Alison Weir points out that Edward III didn't respond to it immediately or with a lot of money or fuss (as far as we know). If it was blackmail, maybe it just wasn't a very good attempt.

If you wanted to make serious money as a courtesan in 19th century England, there was one way to do it that had little to do with the actual work of being a courtesan: you got yourself some wealthy and well-respected clients, and you kept scrupulous records of your assignations, including any letters they may have sent you. Then, once your charms no longer earned you a sufficient income, you got them to pay up for their silence.

Harriette Wilson is one of these enterprising ladies, who eventually published her memoirs; her attempts to blackmail the Duke of Wellington into paying to get the parts about him scrubbed from the book led him to roar, "Publish and be damned!" Others were more forthcoming; biographers of Wilson have been frustrated by the fact that she clearly altered her memoirs depending on who paid up.

The hero of Hamilton wasn't immune to a bit of political sex scandal, as anybody who's seen the musical knows. Hamilton was targeted in 1791; it turned out he'd been having an affair with a married woman, Maria Reynolds, while paying her husband James for his silence.

So far, so normal. But James was involved in a lot of other scams, and when he was arrested for a scheme involving unpaid soldier's wages from the Revolutionary War, he attempted to use his dirt on Hamilton to get himself out of trouble. It didn't work. Hamilton refused to help, and James told Hamilton's enemies that the wage scheme was all the then-Treasury secretary's idea.

Hamilton fessed up to the affair, but provided evidence to them (and to the public, who'd been let into the whole sorry episode) that he'd had nothing whatever to do with the fraud.

The Duke of York's assignations with Mary Ann Clarke became one of those almighty political knots that enters history simply for seeming almost too weird to be true. Clarke attempted to blackmail her ex-lover, the Duke — who led the British army — by threatening to publish his letters. His political enemies took notice, and they discovered that she'd been selling army commissions (meaning, men who wanted a military rank or promotion would pay off Clarke, who would then demand that the Duke give her clients what they wanted).

One of the Duke's enemies, Gwyllym Wardle, launched a parliamentary inquiry in which Clarke stood on the stand for 12 days, sharing saucy details and the Duke's involvement in her scheme.

It was a hilarious, shocking scandal — and it only got more hilarious and shocking when it was revealed that Wardle himself may have bought Clarke's testimony in return for cash payments and (get ready) agreeing to redecorate her house.

Clarke went to live the rest of her life in France, and published a book saying she'd only revealed the Duke's secrets for money. She lived happily ever after.

Marie Antoinette's reputation these days is as something of a frivolous idiot caught up in an exceptionally bad situation. At the time of her death, though, a combination of criminality and incompetence had landed her a more sinister reputation.

A group of London blackmailers, it seems, threatened her husband Louis XVI with the publication of pamphlets with all kinds of scurrilous rumors about the Queen, including allegations regarding horrible things like sexual abuse and bestiality. Louis paid them off.

These pamphlets were the source of myth that the queen had said "let them eat cake," but they weren't the first pamphlets to start rumors about her; a lot of others had been circulating, alleging that the queen was involved in lesbian trysts or had participated in suspicious activities.

But even after Louis paid the blackmailers, the pamphlets were stored at the Bastille by bureaucrats. When the Bastille was stormed during the Revolution, the publications were found, seized, reprinted, and read avidly by everybody. Alas, Louis had paid the blackmailers in vain.

There are few more notably spectacular or brutal women in history than the Empress Cixi, who started out as an imperial concubine and went on to rule China until 1908; she had a life so eventful it'd take about four days to explain it. The bit that's relevant here, though, is that she herself was an astute and merciless blackmailer. She maintained control over China even though her nephew, the Guangxu Emperor, was technically in charge, and used some interesting means to keep him in line.

According to her biographer Jung Chang, when the Guangxu Emperor crossed her, Cixi took and tortured his favorite concubine and her eunuch servants until the girl revealed salacious sexual secrets. The Empress then used the details to keep her wayward nephew in line. Not exactly the best way you get your name in the history books.