What major world event caused Europe to enter a new era called the Middle Ages?

Why did the Saxons hate the normans? When did the first people reach Canada? What main food did the English colonies eat? What change was made by general Joseph hooker as new commander of the union army was to? According to one source 80 percent of the Intel Al-Qaeda collects comes from what? Is the World Series the only time NL teams play AL teams? How long after the civil war did slavery end in the u.s.? What represents the belief used to justify westward expansion of America's borders in the 1800s Monroe Doctrine Manifest Destiny Adams-Onis Treaty or Missouri Compromise? What games did naskapi play? Where can you find a timeline on the cell phone? Who ended the Golden Age of Islam? What four organizations helped to create the Internet? How will the Americans be consoled for their hardships? What are the terms of the embargo act passed by congress? Why was mythology important to lives of ancient Greeks? Movement of a body segment around its longitudinal axis is? Did Ip Man really fight a marine during his lifetime? What was William pitts goal? What age were children taught about nazism? How does the computer misuse act affect a business?