The 100 Years’ War was a conflict between England and France that began shortly after the death of the French king Charles IV in 1328 and went on for more than a hundred years until it ended with the French victory at the Battle of Castillon in 1453.
The 100 Years War is usually called a “war of succession.” When a king dies, the next king is said to “succeed” him. The next king is the dead king’s “successor.”
During the Middle Ages, the English kings owned land inside France. The royal families of England and France were closely related. Sometimes land changed hands because of marriage. For example, the English crown acquired the French province of Aquitaine when Eleanor of Aquitaine married English king Henry II in 1154.
In 1308, Isabella, the daughter of French king Philip IV, married king Edward II of England. When her brother (Charles IV of France) died in 1328 without leaving a son to inherit the throne, the most direct male descendant was Isabella’s son Edward. He was the grandson of the French king Philip IV, but he was also King Edward III of England.
The French didn’t want to put the English king on the throne of France, so they chose a nephew of Philip IV, Philip of Valois. He became King Philip VI of France.
At first, Edward III accepted the decision. In 1337, however, when Philip threatened to take back Aquitaine for the French, Edward declared war. In 1340, Edward III quartered the arms of England and the arms of France and declared that he, not Philip, was the rightful king of France.
The 100 Years’ War was interrupted by various truces, but it disrupted both countries for a very long time. This is the war in which Joan of Arc fought.