It is first built by Philip II (House of Capet) in medieval time (late 12th century) as a fortress for defensive purposes. It was at suburb of Paris at the time then. The remnants of the fortress still remains in the basement of the museum today.
During the Hundred Years' War, the Kings were costumed to live away from the capital. In 14th century Charles V (House of Valois) turned it into a royal resident. Then in 1954, Francis I (House of Valois) hired Pierre Lescot to renovate it into renaissance style. Lescot demolished the west wing and rebuilt it, which is now known as the Lescot wing, oldest part of the Louvre. The major work continued into the rein of the next King, Henry II.
In 1572, on the wedding day of Henry and Margaret, Massacre of Saint Bartholomew's Day started within the walls of Louvre. Thousands French Protestants were brutally murdered by Catholics.
20 years later, Henry became Henry IV (House of Bourbon). He wanted to connect Louvre and the newly built Palais des Tuileries by Catherine de' Medici (Queen of France) in 1564. So Grande Galerie was built. At its completion, Henry IV made it a public gallery with artists living on the lower floor of the building.
In early 17th Century, Louis XIII(House of Bourbon) began contructing north wing and extended the west wing with what now call Parillon de l'Horloge, as there is a clock on it. and Louis XIV(House of Bourbon) continued on with the east wing (main entrance) and doubling the length of the south wing. This doubled the size of what now call Cour Carrée. He never finished them, they were left roofless for near a century.
Then in French Revolution comes and this time round Napoleon was the man in power. Under Napoleon, Cour Carrée was finally completed and Arc de Triomphe du Carrousel was built between the two west wings. Under Napoleon II in Second Empire in 1852-1857, the north and south wings were built, now known as Richelieu and Neon wings. They both are built in Neo-baroque style. At this point, the grand plan for Louvre was finally "completed". Then in 1871, Palais des Tuileries was burnt by the French Commune. The west side of Louvre is left open since. In 1882, under Napoleon III in Third Empire, the ruins of Tuileries was cleaned up; Thus Cour du Carrousel and Cour Napoleon were created.
Of course, the pyramid, its underground lobby and inverted pyramid were completed in 1993, designed by Leoh Ming Pei. It turned out to be a huge success, and serving as the symbol of modern day Louvre Museum.
