Louis VI, called "The Fat" was born in 1081 and died in 1137. He was king of France (1108-1137), son and successor of Philip I; he was married to Adelaide of Savoy. Almost his entire reign was spent in subduing the robber barons, who preyed on the environs of Paris but were finally forced to yield to royal authority. For some 20 years during the period from 1109-1135, Louis waged war against Henry I, the Norman king of England, and against Henry's son-in-law, Holy Roman Emperor Henry V; he successfully repelled an invasion by Henry V in 1124. Louis greatly strengthed the royal power in France, granted benefactions to the church and privileges to towns, and became known as the protector of the peasants and as a fearless military leader.

Called Louis the Fat because by middle age he was so large he had to be helped onto a horse, King Louis VI nevertheless managed his realm effectively, given his limited resources, and even managed to waddle into combat himself. He was more ambitious and energetic than was his father, and he was the first king of the Capetian line to have success in compelling obedience from his barons. At least occasionally.

Louis spent much of his reign at war, either with rebellious vassals, or with foreign enemies. He was not always successful in these campaigns, but he never lost disastrously and he was successful often enough that by the end of the reign he, too, had added a bit to the royal demesne. As one example, the counts of Flanders were nominally the vassals of the king, but they had long been independent. In 1127, the Count of Flanders was murdered. Louis acted quickly, occupying the country and installing his own choice as the new count. He then returned to France. His man was soon driven out, but his intervention established a definite French influence and reminded everyone that he was the suzerain of the Flemings. This doesn't sound like much, but it was more than previous kings had managed.

References:
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