How far back in time can you understand English?

An experiment in language change

A man takes a train from London to the coast. He’s visiting a town called Wulfleet. It’s small and old, the kind of place with a pub that’s been pouring pints since the Battle of Bosworth Field. He’s going to write about it for his blog. He’s excited.
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He arrives, he checks in. He walks to the cute B&B he’d picked out online. And he writes it all up like any good travel blogger would: in that breezy LiveJournal style from 25 years ago, perhaps, in his case, trying a little too hard.
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But as his post goes on, his language gets older. A hundred years older with each jump. The spelling changes. The grammar changes. Words you know are replaced by unfamiliar words, and his attitude gets older too, as the blogger’s voice is replaced by that of a Georgian diarist, an Elizabethan pamphleteer, a medieval chronicler.
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By the middle of his post, he’s writing in what might as well be a foreign language.
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But it’s not a foreign language. It’s all English.
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None of the story is real: not the blogger, not the town. But the language is real, or at least realistic. I constructed the passages myself, working from what we know about how English was written in each period.1
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It’s a thousand years of the English language, compressed into a single blog post.
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Read it and notice where you start to struggle. Notice where you give up entirely. Then meet me on the other side and I’ll tell you what happened to the language (and the blogger).

https://www.deadlanguagesociety.com/p/how-far-back-in-time-understand-english

How far back in time can you understand English?

^{Colin Gorrie (Dead Language Society)}