When he overthrown Louis the 18th what did he set up?

When Napoleon Bonaparte overthrew Louis XVIII in 1815 during the period known as the Hundred Days, he reestablished himself as Emperor of the French. This marked the end of the Bourbon restoration and the brief return of Napoleon to power after his initial abdication in 1814. His return was met with mixed reactions, leading to the eventual defeat at the Battle of Waterloo and his final exile.