From the National Archives:
This broadside was produced in January 1867 by a “regulator” group—a paramilitary organization formed to intimidate Southern blacks and whites sympathetic to them. It was nailed to the door of a free person’s house. A U.S. Army lieutenant wrote that the “circulars” were being “read to the colored people” by men who claimed they had been appointed to “see the rules enforced.”
Does NARA know where this circular came from?
Hi, Henry. That National Archives is awfully confusing. The image shows up on its Wiki (linked to above), and credited to “National Archives, Records of U.S. Army Continental Commands, 1821–1920.” But if you go to that site online, this particular document does not show up as an available online record:
http://research.archives.gov/search?desc-rg=393&pg_src=group&data-source=all
All of which is to say, I don’t know!