The most luxurious hotels in the 6th Arrondissement of Paris have served as homes of royalty and gathering places for artistic and intellectual luminaries of history, from 18th-century philosopher Denis Diderot to 19th-century writer Oscar Wilde to 20th-century film icon Lauren Bacall. Here, we've spotlighted the very best luxury hotels in the 6th Arrondissement, among the most fashionable neighborhoods in Paris.