The Hundred Years' War was a fierce collection battle between the English and the French. The wars were fought to win the French land.
There were many things that helped England win the early battle, and one thing that majorly helped support the overall French victory.
One of the keys to England's early victories was the longbow. Unlike the normal bow, the longbow could shoot farther and pierce the metal armor of knights. This allowed them to win some very decisive victories in the early days of the war.
France came into some major trouble when Orleans was laid under siege by England, but help was coming from an unlikely source whose name world go down in history.
That help came in the form of a teenage farm girl. She had visions from God and eventually an angel came and told her to fight for France in the war. After that, she made her trip to Orleans. At first the king did not believe her, but after telling him something she could not have known he gave her a high ranking place in the military. Due to her power from God, she won many battles using her knowledge of the future.
Sadly she was injured and caught during battle in 1429 by the Burgundians. She was then sold to the British as a war criminal. When the British learned she was a girl they convicted her of heresy and witchcraft, and burned her at the stake.
The French finally defeated the British and drove them out of France in 1453 due to a myriad of reasons including the Duke of Burgundy switching sides and the cannon. Joan of Arc helped cause the French to unify into a single cultural identity. In 1920, the Roman Catholic Church declared Joan of Arc a saint.