You hear about them so much, you feel like you know them: the Kings Louis of France (how do you make "Louis" plural?!). But how well do you know them? Do you know which one had a mistress (if you guessed all of them, you're probably close to correct). Who had the famous mistress Comtesse du Barry? Which was beheaded? Who ruled the longest? Who was the last King Louis? And why does anybody still care?