The document discusses the period of European history from 600-1200 CE. It provides context around debates over whether this era should be called the "Dark Ages." Key developments included invasions of groups like the Vikings, the rise of feudalism, and increased power of the Catholic Church. The Church grew wealthy and modeled itself after the Roman Empire, spreading Christianity while also competing for power with rulers. Overall population grew significantly from 35 to 80 million between 1000-1300 CE.