Louis VI (1081–1137), king of France, was known as Louis the Fat. He was the only son of Philip I and Bertha of Holland. While a youth, Louis was named count of Vexin, a strategic area on the Norman border. He proved to be an energetic warrior, and after 1100 he gradually took over military leadership from his lethargic and corpulent father.

In 1108, Louis acceded to the throne, and in 1115 he married Adélaïde de Maurienne, whose uncle became Pope Callistus II in 1119. Unlike Philip I, Louis VI maintained good relations with the papacy. He was especially popular with the clergy of northern France because of his defense of churches and monasteries against the depredations of the lords of the Île-de-France. One of his friends and collaborators was Suger, Abbot of St. Denis, who wrote a laudatory biography of the King and helped to instill in Louis his strong sense of feudal suzerainty.

Extension of Personal Rule
Most of the royal lands were located in the Île-de-France, and the roads connecting these scattered possessions were commanded by castles whose lords terrorized the country. The interests of both the monarchy and the church demanded that the lords be brought to justice. Acting as the defender of peace, Louis systematically summoned offenders to his court and then enforced its judgments with vigorous military action. It took years to subdue such rebellious lords as Thomas de Marle and Hugues du Puiset. By his death, however, Louis had pacified the Île-de-France, turned the local seigneurs into loyal vassals, and given new prestige and credibility to royal justice.

Louis exercised little authority outside the Île-de-France, but his energy and military prowess made him a respected figure, and most of the great feudatories rallied to him to help repulse an invasion led by Emperor Henry V in 1124. Louis failed when he intervened in Flanders in 1127, and he barely held his own against the powerful Count of Blois. He often warred with Henry I of England, who was also Duke of Normandy. Louis was unable to prevent Henry from strengthening his position in France through the marriage of his daughter Matilda to Geoffrey "Plantagenet," Count of Anjou (reigned 1129–1151).

Louis VI had to overcome an effort by the Garlande family to turn the greatest royal offices into hereditary possessions. Louis foiled this attempt in 1127 by suspending the chancellor, Étienne de Garlande, and by naming his own cousin, Raoul of Vermandois, seneschal. Raoul and Suger were the major royal advisers in the last decade of the reign. The death of Henry I enabled Louis to enjoy two years of tranquillity before he, too, died, in Paris on Aug. 1, 1137. Earlier in the year the dying Duke William X of Aquitaine had entrusted Eleanor, his young heiress, to the care of Louis, who had promptly married her to his son, the future Louis VII (Henneman, John B. "Louis VI (France) (1081–1137)." Encyclopedia Americana. Grolier Online, 2012. Web. 31 Jan. 2012)