"The King has taken my wife, and I am the one sent away."
That, roughly, is what the Marquis de Montespan discovered around 1668 when Françoise de Rochechouart became Louis XIV's most powerful mistress at the Palace of Versailles. He did not take it quietly. He staged a mock funeral for his wife, dressed his carriage in cuckold's horns, actual antlers bolted to the roof, and made the kind of public scene that Versailles absolutely did not tolerate. His reward: swift exile to his provincial estates, where he stayed, loudly furious, for the better part of two decades.
His reaction was, by the court's own logic, entirely wrong.
Here's how the math worked inside Versailles circa 1670. The maîtresse-en-titre, the official mistress, was a formal appointment, not a scandal. Her parents gained access, her brothers gained commissions, her cousins gained introductions. The family unit was understood to benefit collectively. Husbands, in most cases, were expected to read the room: accept a generous pension, look elsewhere for entertainment (which most already were, given that noble marriages were dynastic contracts, not love affairs), and stop making noise.
Some husbands played it beautifully. Others quietly leveraged their wife's position for military promotions or land grants and never said a word. The transactional nature of aristocratic marriage in seventeenth-century France meant that many a husband had already been conducting his own arrangements for years before the king came calling. The accounting, in those cases, was roughly square.
What Versailles could not absorb was noise. Outrage was a social crime. The Marquis de Montespan's error wasn't that he was angry, it was that he said so, loudly, in front of people who wrote things down.
Françoise went on to bear Louis seven children between 1669 and 1678, with six surviving to adulthood. The marquis went on to become history's most dramatically self-defeating footnote.
So here's the question for you: if you'd been a nobleman at Versailles with the king's eye on your spouse, what was the actually rational move, and does "rational" make it any less grim? Tell us below.