Final answer:
Europe used religion in governance from 600 to 1450 C.E. with the Catholic Church playing a central role, influencing political power structures and societal norms. Religious legitimacy was key to rulers, which eventually led to the Protestant Reformation, significantly altering European politics and church authority.
Step-by-step explanation:
From 600 C.E. to 1450 C.E., Europe intertwined religion and government, with the Catholic Church wielding vast influence. Christianity permeated every aspect of life, including politics, education, and social order. In 800, Pope Leo III crowned Charlemagne, solidifying the Church's power in state affairs.
The Vatican, especially post-reformation, held tremendous control over European societies, dictating laws and customs rooted in religious doctrine. Conversely, Muslim rule in Spain fostered a multi-religious society, albeit under Islamic governance. Worldly governments heavily relied on religious legitimacy to rule, echoed later by the Protestant Reformation challenging Catholic dominance, leading to major religious and political shifts across Europe.