Short answers, pulled from the story.
King Louis XIV commissioned the expansion of the Palace of Versailles, transforming it from a hunting château built by Louis XIII in 1623 into a full royal residence through several construction phases from 1661 to 1715. Louis XIV moved the seat of his court and government to Versailles in 1682, making it the de facto capital of France.
Louis XIV used Versailles to centralize royal power and draw the French nobility away from their provincial power bases, offering prestige and royal patronage under strict court etiquette. After the Fronde revolts of 1648-1653, he was determined to rule alone, and Versailles gave him a seat of government entirely under his control.
In October 1789, a crowd of several thousand people marched from Paris to Versailles and compelled Louis XVI and the royal family to return to Paris. The palace was then closed, its paintings and sculptures transferred to the Louvre in 1792, and its royal property sold at auction in seventeen thousand lots between 1793 and 1794.
Two of the three treaties of the Peace of Paris ending the American Revolutionary War were signed at the Palace of Versailles on the 4th of September 1783, when Spain and France signed separate agreements with Britain. The Treaty of Versailles formally ending the First World War was also signed in the Hall of Mirrors in June 1919.
The Hall of Mirrors is a long gallery at the westernmost part of the palace, built from 1678 to 1681 on the site of a terrace between the king and queen's suites. It is clad in marble and features 578 mirrors facing 17 windows, with a ceiling fresco by Charles Le Brun depicting the first 18 years of Louis XIV's reign in 30 scenes.
About 15 million people visit the palace, park, or gardens of Versailles every year, making it one of the most visited sites in the world. The palace has been managed by the Public Establishment of the Palace, Museum and National Estate of Versailles under the French Ministry of Culture since 1995.