Louis XVIII , known in his youth as the Comte de Provence, was the other brother of Louis XVI, and often his nemesis. He was not a bad looking man; his eyes radiate intelligence. Later he put on so much weight and had such a problem with gout, but then he was a gourmande, relishing the delights of the table. His chef at Versailles was equal to none.
As Comte de Provence, he was a consummate plotter. It is alleged that he had a private printing press at Versailles which produced pamphlets against Louis XVI and Marie-Antoinette. Provence and his wife, Madame, were certainly responsible for circulating the gossip about Marie-Antoinette, slandering her virtue as much as possible. Provence thought that he was better qualified to rule than Louis XVI and so spent his life in a jockeying for power by trying to undermine his brother's rule. Also, Provence often intrigued against Louis XVI during the Revolution, corresponding with revolutionaries. How much his plotting contributed to the fall of the monarchy is explored in the novel Madame Royale.
Louis XVIII was a stickler for etiquette, unlike Louis XVI, who was more easy-going. Even at exile in Courland and England, when they had few resources, Louis XVIII insisted upon the full court etiquette as if they were all still at Versailles. This was beneficial in the long run, because they were able to function as a royal household when restored to the Tuileries. He was clever with money and made certain that all his family were well-provided for when he died. He was a brilliant Latin scholar and could have taught the classics at a university.
Napoleon at one point wrote to Louis XVIII in exile, begging him to renounce his claim to the throne. Louis responded with a "no" saying, "I may have lost my country, I may have lost my possessions, but I still have my honor, and with it I will die." On another occasion he said, "In this century, it is more glorious to merit a scepter than to wield it." In 1814 upon his return to France, the fat, gouty King was introduced to Napoleon's generals. They were so used to being shouted at by Napoleon that the charm and unctuous courtesy of Louis XVIII disarmed them, especially the fact that he knew their names and anecdotes of their exploits in battle. (That was the old-fashioned royal training.) He declared that whatever they had done for France on the field of battle, they had done for him. He won most of them over completely and they swore allegiance to him, although some later rejoined Napoleon during the Hundred Days.
Because of his liberal politics, Louis XVIII was known as "The Crowned Jacobin" and "King Voltaire." After Napoleon's defeat of Waterloo, it was only the intervention of Louis XVIII that kept the allies from totally ravaging France in revenge. The Prussians threatened to blow up the Iena bridge in Paris, until Louis threatened he would come over and sit on it. His favorite author was Horace, whom he quoted extensively. He did not actively practice his faith for over thirty years, which caused his niece Marie-Thérèse-Charlotte to have great anxiety over the state of his soul. The princess prevailed upon the old king's favorite, the attractive brunette Madame du Cayla, with whom Louis XVIII played backgammon, to get him to go to confession. (This was a hard thing for Thérèse since she despised Madame du Cayla.) At the moment he died in 1824, the courtiers ran from the room to greet the new king, leaving the faithful valet of Louis XVIII weeping alone by the corpse of his master.