Learn English – Origin of “No, a thousand times no”

How about "thousands" of instances of its usage? I can't resist the irony! (Add your contribution!)

• If I've told you once, [please consider] I've told you a thousand times. - just now
• If I've Told You Once, I've Told You 1,000,000,000 Times - 2010
• If I've told you once, I've told you countless times - 2002
• Dear Rocker in Constance: If I've told you pinheads once, I've told you a thousand times — anybody who listens to the Beatles in 1995 is not only living in the past, he's brain dead! - 1995
• I told you once, Hopkins, I told you million times - 194?
• If I've told you once I've told you five thousand times - 1941
• If I have told you once I have told you ten dozen times - 1930
• If I've told you that once, I've told you thrice — I've told you a thousand times - ?1927?
• don't you know that I not only told you once but, in response to repeated importunities from you, that I told you several times - 1919
• if I said to you once, don't touch confiscated property, I told you so ten thousand times - 1866
• once is as good as if I had told you a thousand Times over - 1735

As a @FumbleFinger's once said:

It's just a standard speech device that people reinvent repeatedly

It is a reference to Helen of Troy. She was said to be so beautiful that, when she was abducted, a fleet of a thousand ships set sail to win her back from Paris, sparking the Trojan Wars.