A number of pages on the Internet, including on sites hosted by the National Archives and the National Park Service, attribute these words to the great abolitionist Frederick Douglass:
Once let the black man get upon his person the brass letter, U.S., let him get an eagle on his button, and a musket on his shoulder and bullets in his pocket, there is no power on earth that can deny that he has earned the right to citizenship.
That bugged me, first, because the quotation contains a grammatical error. “U” and “S” are letters plural, not “letter” singular. There also seems to be an “and” missing after the final comma.
Were those errors really Douglass’s, I wondered? I tracked down the source of the quotation in the scholarly, multivolume work, The Frederick Douglass Papers, edited by John W. Blassingame and published by Yale University Press. Series One, Volume 3, page 596, contains the full quote this way, from a speech delivered in Philadelphia on July 6, 1863:
Once let the black man get upon his person the brass letters U.S.; let him get an eagle on his button, and a musket on his shoulder, and bullets in his pocket, and there is no power on the earth or under the earth which can deny that he has earned the right of citizenship in the United States.
That seems to settle that Douglass did say “letters” and “and.” And it also reveals another phrase which even many sources that get most of the quote right, like the Library of Congress, sometimes leave out: his reference to there being no power “under the earth” capable of denying a Black soldier’s citizenship.
One can almost imagine Douglass, one of history’s great orators, pausing and looking down towards hell as he uttered that sardonic phrase. If he did, the rhetorical flourish would better explain why, according to the transcript in the Frederick Douglass Papers, the sentence was followed not only by applause from the audience, but by laughter.