Why HundredYears' War started?

Why Hundred Years’ War started?

In Japan, it is generally said that the succession-to-the-throne problem of France caused Hundred Years’ War. Some people say that Flandre problems or Guyenne problems caused it. But it does not have enough factors. Today I’ll tell you an interesting opinion of its main factor. I referred to Mr. Kido’s commentary. His book, Hyakunensensou –tyuseimakki no eifutu kankei-, was very helpful. The war is source of very complicated relations between England and France.

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In 1066, William, Duke of Normandy, became an English king. As Duke of Normandy, he remained a vassal of the French King, and was required to swear fealty for his lands in France. From this time, English kings had to continue the relationship. They sometimes fought against French kings and tried to be equal footing with them.

In 1259, a treaty was concluded.  It settled disputes between them. That is because then the English king is from Anjou, which is one of the French counts. Anjou has very big lands in the southwest part of France. Both countries thought the lands were their territory, so it is necessary to decide it.

But the treaty had some problems. First, their territories were not clear. Second, Anjou had to make its vassals help French kings, when English kings fought with them. It was impossible. Third, the English king swore fealty to the French king clearly again. English kings detested doing so after that. However, French king was angry that English kings did not swear fealty.

It is this treaty that is the main factor of the war. The problems made both countries angry with the other. When they cannot put up with them any longer, French king changed at just the right moment.