The years 1000 to 1500 saw the gradual extension and consolidation of the power of the French kings , accompanied by the growth of a centralized administrative system and bureaucracy. These factors also determined their foreign policy, which was chiefly concerned with restricting papal interference in French affairs and checking the English kings' continuing involvement in French territory. While progress towards these goals was remarkably steady and single-minded, there were setbacks, principally in the seesawing fortunes of the conflict with the English.

Surrounded by vassals much stronger than themselves, Hugues Capet and his successors remained weak throughout the eleventh century, though they made the most of their feudal rights. As dukes of the French, counts of Paris and anointed kings, they enjoyed a prestige their vassals dared not offend - not least because that would have set a precedent of disobedience for their own lesser vassals.

At the beginning of the twelfth century, having successfully tamed his own vassals in the Île-de-France, Louis VI had a stroke of luck. Eleanor , daughter of the powerful duke of Aquitaine, was left in his care on her father's death, so he promptly married her off to his son, the future Louis VII.

Unfortunately, the marriage ended in divorce and immediately, in 1152, Eleanor married Henry of Normandy, shortly to become Henry II of England. Thus the English crown gained control of a huge chunk of French territory, stretching from the Channel to the Pyrenees. Though their fortunes fluctuated over the ensuing three hundred years, the English rulers remained a perpetual thorn in the side of the French kings, with a dangerous potential for alliance with any rebellious French vassals.

Philippe Auguste (1179-1223) made considerable headway in undermining English rule by exploiting the bitter relations between Henry II and his three sons, one of whom was Richard the Lionheart. But he fell out with Richard when they took part in the Third Crusade together. Luckily, Richard died before he was able to claw back Philippe's gains, and by the end of his reign Philippe had recovered all of Normandy and the English possessions north of the Loire.

For the first time, the royal lands were greater than those of any other French lord. The foundations of a systematic administration and civil service had been established in Paris , and Philippe had firmly and quietly marked his independence from the papacy by refusing to take any interest in the crusade against the heretic Cathars of Languedoc. When Languedoc and Poitou came under royal control in the reign of his son Louis VIII, France was by far the greatest power in western Europe.