What's the origin of the Knock Knock joke?

[sub]I have searched Google and the archives but couldn’t find anything…[/sub]

How far back does the knock knock joke go? Is it an American invention? Is there an early recorded joke in written material? Can it be traced to a specific source - maybe an old radio program or something? What’s the most famous one?

I’ve got questions, you hear? Questions!!! :smiley:

I can’t give you any oirigin but I can tell you that they were alive and well in the early thirties. I would hazard a guess that they were as part of a comedy routine a la Abbott and Costello.

Go to Dogplie-----“bang in” knock knock jokes"-------go crazy!

Ezstrete - go where? Will that tell me what the origins are?

http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=78955&highlight=knock+knock+joke

Sorry-------that should have read dogpile.

There’s a lot of stuff under “Knock knock” there

Son of a…

Thanks samclem - I’m not sure why I didn’t find that one…

Thank you as well Ezstrete.