The Abolitionists believed that niggers were as good as white men, and that they ought to be free and allowed to marry white women. They were always holding meetings and “resolving” and publishing articles to say that slaveholders were thieves; and some of them came down to stir the slaves to revolt, and to carry them off to Canada. At first people had tried mobbing them, and the Southern legislatures had put prices on the heads of the worst of them, but neither of these methods seemed to do any good. They had gone on just the same for fifteen years now, and had even gotten so bold as to send petitions to Congress, which had, of course, refused to receive them, — only a terrible old man, ex-President John Quincy Adams, who had been in Congress since nobody could remember when, kept making a disturbance about it and had actually carried his point a while ago. So things went from bad to worse, and naturally the people of the South got more and more angry.
MANASSAS, A Novel of the (Civil) War by Upton Sinclair, 1904, page 20