Why didn't most people learn to read or write in the 1300s?

In those areas where most people could not read, the reason was a lack of cultural emphasis on literacy. But we should not assume most people could not read throughout medieval Europe.

The Byzantine Empire had a primary school system operating at the village level, founded in 425 AD, which continued until 1453 and taught both boys and girls. The Jews and Muslims also had schools where most boys, and some girls, were taught. We have tended to believe anything written by Renaissance writers about the ignorance of the age from which they were so proudly recovering, and much of what they wrote was not true.

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