In 1215, King John, a greedy and cruel man, ruled England. He lost the land previously acquired from France, and denied an appointment of a new archbishop from the Pope. This angered the Pope, resulting in King John and all of England being under interdict. Eventually, the Nobles had enough of the oppressive taxes and forced John to sign the Magna Carta. It gave people rights, made clear the monarch must obey laws, and established due process of law.
We have rights too!
In 1095, Pope Urban II wanted Christians to regain their holy land in Jerusalem. The pope had two main reasons for encouraging this war; to reunite Western and Eastern Europe, and to keep the Christians fighting Muslims rather than one another. The first crusade was the only successful one for the Christians. The Muslims regained control of Jerusalem and kept it throughout the rest of the battles. The Crusades lasted from 1096-1204, and the Christians never won back Jerusalem.
God wills it!
The Plague swept through Europe, killing 33-50% of Europe's population during its height in 1348-1351. People didn't know how to handle the mass amount of death, which resulted in religious and economical crisis. Some people blamed the Jews, others blamed the Church. People would even kill their dogs, believing that they were spreading the disease. In reality, the rats were the cause. All attempts Europeans made to stop the Plague ending up making it worse.
Why would God do this to us?
The Hundred Years' War was fought between France and Britain from 1337-1453. The English King was determined to regain his control in France, and declared himself King of France in 1337. New weapons came along during this war, causing it to seem very one sided at times. In the beginning, England had a strong advantage because of the new weapon; the long bow. After losing several battles, the French began using cannons. By the end of the war, the English had only won a small port in Northern France. Although the war didn't result in much land difference, new technologies emerged.
We must attack! We must protect our land!
This should provide protection for us against invaders.
During the Middle Ages, the Church was more powerful than ever. With new building technologies, people wanted to build large Cathedrals to show their religious devotion and wealth. Romanesque churches had no windows and were dark and gloomy while Gothic churches had large stained-glass windows. Castles were also flourishing and were used for protection until the Hundred Years' War.
Weapons revolutionized throughout the Middle Ages. In 1000-1500 AD, throwing axes and long axes were used in battles. From 1300-1450 AD, people used javelins, hand axes, and spears to fight. Finally, in 1500 AD, swords were used more against cavalry. Bows and arrows also became more prominent because they were cheap, easy to use, and easy to reload.