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How far back in time can you understand English?
(www.deadlanguagesociety.com)
For stuff that's neat. Neat article? Neat video? Neat pic of a bug you saw? All good. Neat meme? Ehhh... take it to the meme subs.
Rules
Shakespeare is modern English. Even that is challenging for most people. Beyond that it's not longer the English we think of (with the heavy French influence).