The reason why manuscripts were so expensive in the early fifteenth century is because the printing press wasn't invented until 1440, meaning that every individual script had to be written by hand.
The worlds population is growing and is overpopulating. This is negatively affecting the worlds biodiversity.
Although the Crusades are popularly viewed as religiously inspired campaigns to recapture the Holy Land, students should recognize them as a result of the social and economic events in Europe between 1000 and 1200. Religious and secular leaders seeking to end the fighting among feudal lords seized upon the Crusades as a means of redirecting that aggression. Feudal knights who would not be inheriting their family properties eagerly enlisted in the Crusades as a way to win wealth or status. The idea of the pilgrimage was a powerful one, and the Crusades were basically armed pilgrimages to the Holy Land. The various Crusades ultimately failed. The sack of Constantinople was a fitting denouement to the whole concept. The interaction with the East brought to Europe not only Arabic translations of Greek texts, but also original Arabic and Iranian scientific and philosophical works.
