What does forsooth in old English mean?

"Forsooth" is not an Old English word. It originated in Middle English, derived from the Old English phrase "for soth," meaning "for truth" or "truly."

In Middle English, "forsooth" functioned as an emphatic adverb, often used to express:

* Emphasis or affirmation: "Forsooth, I tell you, the king is dead!"

* Certainty or assurance: "Forsooth, I have seen the dragon with my own eyes."

* Sarcasm or irony: "Forsooth, you are a brave knight." (Said with a mocking tone)

Today, "forsooth" is mostly used in a humorous or archaic context, often to add a touch of old-fashioned or mock-seriousness to speech or writing. It's rarely used in everyday conversation.