Also, Latin was the Bible Language, until the mid-1950's. Most of the liturgy of the Church, and readings from Bible were done in Latin only.
Few people could read their Bibles, and often they could not understand what was being said in church, they took it "on faith".
The Pope of Rome, ruled all of Christiandom.
After the "Reformation", the Bible was translated into local languages, and then the local common people needed an education to read it.
Protestantism taught that each man or woman could get salvation directly through either faith, or good works, or both. They didn't need the clergy as "intermediaries".
Each local denomination ruled it's own church, made up its own rules, rather than take directions from Rome.
This lead to many problems. But it gave a great boost to modern education, because now schools were more independent from Rome too, and each local area decided what to teach in their schools.
Still, for a long time, most schools had religious instruction, and were supported by church funding. Not until after the American Revolution, did people start talking about separation of church an state.
Public schools were opened, that were supported by local property taxes, or the selling of state land. That really changed education, as then professionals, and secularism replaced "bible" based teachings.
What some people think started in the 20th century, secularism, actually started with te Protestant Reformation, and the allowance for "free thinkers" rather than those who had to accept domination of chuch dogma.
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