Inspired by the question How long is a 'wink'?How long is a 'wink'?, I did some work on the origin of the phrase forty winks. Though the OP at the wink question mentions the phrase, it does not ask about its origin. So I thought I'd ask the question here and post what I've found. I was able to find an antedating not mentioned by any of the usual phrase-dictionary suspects. The most accurate information I found elsewhere was from a post by Ken G in a discussion of the phrase at Wordwizard. Any other insights welcome.