The document summarizes key events of the Medieval period from 800 to the late 1300s. It describes William the Conqueror's Norman Conquest of England in 1066, the feudal system with the King at the top, and the spread of Christianity across Europe. The Crusades launched in the late 11th century to defend Christianity from Islam, involving thousands of European travelers to Jerusalem. While many died, the Crusades lasted over 200 years and led to new technologies and trade routes being developed. The growing population caused sanitation issues which led to the Black Death pandemic. It was a dark time for the Church as innocent people were tortured and killed in the name of finding heretics.