Who is the French monarchs who were executed during the French Revolution?

the french monarch that was killed was King Louis XVI. he, along with many others, were killed in the Reign of Terror. Many of the people that were killed were suspected of plotting against the Robespierre government. about 17000 were killed in all. including some philosophers. thomas Paine was almost killed too until James monroe saved him. others were suspected of supporting the Austria-Prussia alliance about to invade France.