PARIS: God, this is so weird. I can’t stop smiling.
RORY: Good, then it’s a good time to talk about our over-taxed peasants.
PARIS: Oh, let them eat cake.
Paris is referring to Marie Antoinette, the wife of King Louis XVI, and the last queen of France before the French Revolution.
“Let them eat cake” is a phrase popularly ascribed to Marie Antoinette upon being told the peasants were starving and had no bread to eat. The phrase supposedly demonstrates either an indifference to their plight, or a complete lack of understanding of it. It doesn’t fit with what we know of Marie Antoinette, who was quite concerned with the poor, and donated generously to charitable causes.
She almost certainly did not say it. It comes from Jean-Jacques Rousseau’s Confessions (1782), where he mentions a “great princess” who once said it. Not only does he not name the princess, but that part of his autobiography covers the years when Marie Antoinette would have been a little girl in Austria. He may have invented the anecdote entirely.