@Dušan its debatable that our ancestors were illiterate till 200 years ago BUT you have to take in consideration the fact that our own writing language was edited and 5 out of the 49 symbols completely removed. The man one of the many seminars I attended said that those 5 symbols were important for us in a spiritual way (I might be little wrong on this one so do your own research). We know which 5 of them were removed, we just dont know how to pronounce them. In other words, we know how to write it but we dont know how to read it. 5 out of 49 symbols (bukiev) are gone and few others were edited. Thats 10% less “letters” which added to illiteracy without a doubt.
The old Slavic writing system (Staroslovienska bukvica in slovak) was so “primitive” that they had to remove 5 symbols and edit few others to be able to translate the Bible into their new writing system they made.
Mate, I’ve spent around 20+ years reading whatever I could get my hands on about European history. Ofc I dont know everything. The more I know about history the more I realise how little I know but now I know where to look when I stumble upon something I want to know more about.
With all honesty how many of average everyday-people are literate in European history enouh to understand the logic behind it? Not many because people just dont care about education. They get a little bit of info in school system, half of them forgets it right away anyways and 95% of the other half wont use the knowledge anyways. It wont take you long to find few people who dont believe that Slavs had a written language before Christianity. No joke.
The kids in Slovakia spent 2-3 hours in 6th class learning about Slavs. That’s it. I believe you are from Slovakia too so just go and look it up yourself. Soon the people forget completely who they are and then they become truly illiterate. Look around, we are almost there.