Even Old English is pretty much unreadable by most speakers of Modern English. They still used runes rather than Latin letters 1500 years ago, but even transliterated you'd have a hell of a time.

First stanza of Beowulf in Old English, transliterated into Latin characters:

> Hwæt. We Gardena in geardagum, þeodcyninga, þrym gefrunon, hu ða æþelingas ellen fremedon. Oft Scyld Scefing sceaþena þreatum, monegum mægþum, meodosetla ofteah, egsode eorlas. Syððan ærest wearð feasceaft funden, he þæs frofre gebad,weox under wolcnum, weorðmyndum þah, oðþæt him æghwylc þara ymbsittendra ofer hronrade hyran scolde, gomban gyldan. þæt wæs god cyning. ðæm eafera wæs æfter cenned, geong in geardum, þone god sende folce to frofre; fyrenðearfe ongeat þe hie ær drugon aldorlease lange hwile.

It seems painful. I feel that in Romance languages is easier to identify the roots.

Now that I think about it, I have never read Romance text written before the XIII century: Cantigas, Dante, etc.

It has multiple roots, thanks mainly to the Normans. It also has a habit of plundering vocabulary from other languages, to the point where a single thesaurus entry might list synonyms with etymological origins from a dozen different languages. It can also smash affixes from disparate languages together without shame, particularly prevalent as mixes of Greek and Latin.

There is a decent chance that an English speaker with a broad vocabulary would be able to recognize individual words in any foreign language that can be expressed with the ASCII character set.

Oops, I missed that.