Exeter Book
In the Exeter Book, which is in the possession of Exeter Cathedral and was written around the year 990, there are many riddles. Here is one.
"I am a wonderful help to women, the hope of something good to come. I harm only my slayer. I grow very tall and erect in a bed; I am shaggy down below. A very comely peasant's daughter, a proud maiden, dares sometimes that she grips at me, rubs my red skin, plunders my head, confines me in a stronghold. She soon feels
my meeting, she who forced me in, the curly-haired woman. I bring tears to her eyes."
The answer is of course "an onion". From this we can surmise that the English sense of humour has changed very little in a thousand years.
(Original text: "Ic eom wunderlicu wiht wifum on hyhte neahbuendum nyt; nægum sceþþe burgsittendra nymthe bonan anum. Staþol min is steapheah stonde ic on bedde neoðan ruh nathwær. Neþeð hwilum ful cyrtenu ceorles dohtor modwlonc meowle þæt heo on mec gripe ræseð mec on reodne reafath min heafod fegeð mec on fæsten. Feleþ sona mines gemotes seo þe mec nearwað wif wundenlocc. Wæt bið þæt eage.")