Short answers, pulled from the story.
Louis XVIII was King of France from 1814 to 1824, with a brief interruption during the Hundred Days in 1815 when Napoleon returned to power. He was born on the 17th of November 1755 and died on the 16th of September 1824, making him the last French monarch to die while still reigning.
Louis XVIII fled France in June 1791 during the French Revolution and spent twenty-three years in exile. The Revolution abolished the monarchy in 1792, and Napoleon's rule from 1799 to 1814 prevented any Bourbon restoration. He lived successively in Prussia, Russia, Poland, Sweden, and England before Allied forces defeated Napoleon in 1814 and placed him on the throne.
The Charter of 1814 was France's new constitution issued by Louis XVIII upon his restoration, containing seventy-six articles. It established a bicameral legislature with a Chamber of Deputies and a Chamber of Peers, guaranteed freedom of religion and a degree of press freedom, and restricted voting to the ninety thousand citizens who paid over one thousand francs in annual taxes and were over the age of forty.
Napoleon escaped from Elba on the 26th of February 1815 and landed near Cannes on the 1st of March with roughly one thousand troops. Louis XVIII fled Paris on the night of the 19th of March after the army outside the capital defected to Napoleon. Louis took refuge in Ghent until Napoleon's defeat at the Battle of Waterloo on the 18th of June 1815, after which Louis returned to France.
The White Terror was a wave of anti-Napoleonic violence in southern France following the second restoration in 1815, involving the purge, execution, and assassination of Napoleonic officials. Between an estimated fifty thousand and eighty thousand officials were removed from government. Louis XVIII's government also officially executed Napoleon's Marshal Michel Ney in December 1815 for treason.
Louis XVIII was the last king or emperor of France to die while still holding the throne, a distinction he holds uniquely among post-1774 French monarchs. His brother and successor Charles X abdicated in 1830, Louis Philippe I was deposed in 1848, and Napoleon III was deposed in 1870. Louis XVIII was interred at the Basilica of Saint-Denis, the traditional necropolis of French kings.