To whit: Chaucer - Shakespeare - Coleridge.

"The Rime of the Ancient Mariner" is a classic sprinkled through with archaic words and forms unfamiliar to the average reader, basically readable but when was the last time you heard the past-tense of speak used as "spake" or ran into the word "wist"? Shakespeare you have to practice at, the archaisms and odd sentence structures are so common, but once you develop the ear for it, it's kind of nice. Chaucer's a difficult read for the average American, the language having drifted so far in the intervening centuries, but if you've ever listened to it read in the correct time-period pronunciation, you'd think they were speaking an alien language:

"Whan that Aprill, with his shoures soote
The droghte of March hath perced to the roote
And bathed every veyne in swich licour,
Of which vertu engendred is the flour;
Whan Zephirus eek with his sweete breeth
Inspired hath in every holt and heeth
The tendre croppes, and the yonge sonne
Hath in the Ram his halfe cours yronne,
And smale foweles maken melodye,
10 That slepen al the nyght with open eye-
(So priketh hem Nature in hir corages);..."