We batted around whether this quote was real or not quite a bit on another thread. I think it's real.
To summarize the evidence for the quotes' authenticity, we know it was supposed to have taken place on December 4, 1866 in Lee's office at Washington College. We have confirmation from Major Giles Cooke and two students, John Graham and J. W. Ewing claimed to have witnessed the quote. What we didn't have was anything from the principals, Lee and Lord Garnet Wolseley.
@cash found it hard to believe that Wolseley would not have used the quote in some of his writing....either about Lee or about Forrest. This is an explanation of why we don't have anything on the quote from Wolseley.
Lee wrote to another Englishman in August, 1866. Lee responds to a request to publish parts of their conversation. On the envelope which was found on Lee's desk after his death is written:
"Herbert C Sanders asks permission to publish his conversation with me August 22d - Refused"
In the letter Lee wrote that their conversation was "
was entirely for your own information, and was in no way intended for publication....I have an objection to the publication of my private conversations, which are never intended but for those to whom they are addressed. I cannot, therefore, without an entire disregard of the rule which I have followed in other cases, and in violation of my own sense of propriety, assent to what you propose. "
That would explain the lack of the use of the quote by another English visitor. The entire letter can be found in
Recollections and Letters of General Robert E. Lee by Captain Robert E. Lee, Hi
s Son.