Was "fong" a Middle English word?

I just watched the movie A Knight's Tale, and the character Wat repeatedly threatens to "fong" people (as in "I'll fong you," clearly meaning some kind of bodily violence.)

There are claims around the internet that "fong" is an "actual word from old English" (sic, presumably meaning Middle English) meaning "to kick".

However, I can find no entry for it in the OED, nor in the Middle English Dictionary.

Is there any basis for the claim that "fong" is a Middle English word meaning "to kick"?

Yes, there's some basis for the claim. The Middle English Dictionary gives fongen (-en being an infinitive ending) with a bunch of meanings, the last being:

10. To attack (someone); to molest.

[link]

So, not exactly kick; and it's not the word's primary meaning (not even close); but I think it's enough to make it plausible that the filmmakers were aware of the word, and did not simply invent it coincidentally.

In the film, "fong" seems to be used by one of the characters (Wat) to mean "inflict violence, eg kick", but also as a substitute for fuck, in the swearing sense (rather than the sexual act). From IMDB:

Wat: Uh, betray us, and I will fong you, until your insides are out, your outsides are in, your entrails will become your extrails I will w-rip... all the p... ung. Pain, lots of pain.

and

Wat: All right, I'm about this fonging close mate! I swear to God, Quaisimodo! I oughta...

I think it's really just a humorous word, and there's nothing more to it than that.