Greek mythology is more widely alluded to than even the Bible. Unlike other countries' culture, Greek mythology is universally recognized, understood, and constantly alluded to. Greek mythology impacts poets, writers, movie makers, authors, and the works of art they all produce. Accordingly, their works of art in turn influence others.
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There was little separation of church and state in the middle ages. Besides being royal or having a title, some of the highest ranks in society you could achieve were within The Church.
Additionally, performing certain rites and receiving different ordinances were some of the key ways monarchs could keep up appearances and have a positive reputation with their citizens and peers.
1)There was a spike in population and increased health
(extra fact)Horse-drawn seed press was perfected
2) The passing of the Enclosure laws