Louis XI the Prudent (French: Louis XI le Prudent) (July 3, 1423 – August 30, 1483), also informally nicknamed l'universelle aragne (old French for "universal spider"), was a King of France (1461 - 1483). He was the son of Charles VII of France and Mary of Anjou. He was a member of the Valois Dynasty and was one of the most successful kings of France in terms of uniting the country. His 22-year reign was marked by political machinations, resulting in his being given the nickname of "universal spider".

Born at Bourges, Cher, Louis despised his father and attempted to depose him on several occasions. However, it was only on his father's death in 1461 that he was able to take the throne.

His marriage on June 24, 1436 to Margaret, daughter of King James I of Scotland, gave Louis XI an interest in English affairs, and he schemed to restore King Henry VI of England and his Lancastrian heir to the throne - partly because his arch-enemy, Charles the Bold of Burgundy was allied with the Yorkists. Louis gained the upper hand in his feud with Charles, and brought about his death in 1477. A candid account of some of Louis' activities is given by the courtier, Philippe de Commines, in his Memoires of the period.

King Louis XI married strategically a second time on February 14, 1451 to eight-year-old Charlotte of Savoy (1443- December 1, 1483). Their marriage would not be consummated until she was fourteen and their children were:

• Anne (April, 1461 - November 14, 1522)
• Jeanne (April 23, 1464 - February 4, 1505)
• Charles VIII (June 30, 1470 - April 8, 1498)

By war, by cunning and with sheer guile, Louis XI overcame France's feudal lords and at the time of his death in the chateau at Plessis-lez-Tours , he had united France and laid the foundations of a strong monarchy.

Louis XI was a superstitious man who surrounded himself with astrologers. Interested in science, he once pardoned a man sentenced to death on condition that he serve as a guinea pig in a gallstone operation.

Louis XI was succeeded by his son, Charles VIII.