The Hundred Years' War was fought between France and England during the late Middle Ages. It lasted 116 years from 1337 to 1453. The war started because Charles IV of France died in 1328 without a son. Edward III of England then believed he had the right to become the new king of France through his mother.
The French did not want a foreign king, so Philip VI of France said he ought to be king because by the Salic law women could not rule or transmit the right to rule to their sons. The two countries went to war because of this disagreement.
At the beginning of the war France was the stronger of the two countries. France had about 17 million people while England had only about 4 million people. France had an alliance with Scotland against England, and England tried to ally with parts of the Low Countries. The English won a great victory at sea in the Battle of Sluys in 1340 which prevented France from invading England. After that the war was fought almost totally in France.

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