There were a lot of very stupid monarchs running around during the eighteenth and nineteenth centuries, but, in the Amateur Historian's opinion, the award for "Wow, I Hope That Was the Fault of Inbreeding" goes to Marie-Caroline, queen of Naples.

Marie-Caroline was not a fan of Bonaparte, who she saw as a parvenu, undeserving of a place among all the Hapsburg-jawed monarchs feasting at the European banquet table. Moreover, she was the sister of Marie-Antoinette and never forgave France for killing off her favorite sibling. Therefore, Marie-Caroline (who ran Naples while her indolent husband went slumming) liked to pit Naples against France whenever the other nations were feeling up to forming a new coalition. However, Marie-Caroline did not seem to learn, as each coalition got their royal backsides handed to them with a side-helping of localized republican uprisings. Marie-Caroline actually lost her kingdom twice thanks to her ill-informed attempts at trying to make Naples into a world power (which royally pissed off everyone in Naples) and at fighting the French (which pissed off Napoleon Bonaparte, which is never a good idea).

After the collapse of the second coalition, Marie-Caroline apparently learned nothing and tried again to a. make Naples (which hated her) a world power and b. defeat Bonaparte. This led to quite possibly one of the stupidest stunts she could have pulled: trying to flatter Napoleon and therefore France into submission while forming a "secret" alliance with Great Britain. Or course, Marie-Caroline did an extremely poor job of covering her tracks and did not appear to notice that Napoleon had one of the best spy networks in all of Europe (coming in a very, very close second to Britain, who simply had more money to buy off officials and the like).

Napoleon sent her a very pointed letter, which she unwisely ignored: "Your Majesty has already lost her kingdom twice, would she like to lose it a third time?"

She did.