On or about 20 September 1843, JS replied to a letter from governor with news regarding threats to the in , Illinois. Responding to JS’s earlier concerns regarding a possible invasion of Illinois by Missourians seeking to arrest JS and destroy Nauvoo, Ford had reassured JS that he intended to prevent any invasion of the state but also stated that he believed there was little danger of any outright hostilities. However, conditions in , Illinois, had deteriorated and JS now feared that the county’s politically active Anti-Mormon Party might conspire with Missourians to seek his arrest.

Anti-Mormon Party members were outraged at the failure to extradite JS to in late June and the outcome of the congressional and county elections held in early August. In response, they held a public meeting in , Illinois, on 19 August. After a series of speeches, the group appointed six men to draft resolutions expressing its will, which were publicly read and adopted at a second meeting on 7 September. The preamble and resolutions accused JS and his followers of “entertaining the most absolute contempt for the laws of man” and cited JS’s recent evasion of extradition as the chief example of this contempt. The resolutions bemoaned “mock laws” in Nauvoo that the group believed prosecuted dissenters and shielded criminals. While they claimed that they would ordinarily condemn “anything like lawless violence, without justifiable cause,” the Anti-Mormon Party members swore that if they failed to “obtain speedy redress from the laws of the land,” they would “take summary and signal vengeance upon them [the Latter-day Saints] as a people.” The resolutions were published in the 13 September issue of the Warsaw Message.

JS received ’s letter on 18 September, a few days after news of the public meeting in reached . The next day, JS gave the letter to his scribe to draft a response. The resulting letter condemned the Anti-Mormon Party’s resolutions and denied their accusations. The letter also stated JS’s belief that all true citizens would oppose this “mobocratic insurrection” and affirmed that JS and the Saints were law-abiding people who supported Ford.

There is some confusion regarding when wrote JS’s response. JS’s 19 September journal entry, recorded by his private secretary, , states that JS gave ’s letter to Phelps, who “answe[re]d it dated 20,” which could imply that the letter was completed that day but dated forward to 20 September. However, Richards likely wrote this entry sometime after the fact and may have been merely noting that the letter was completed on 20 September. Phelps appears to have dated the featured version 21 September before correcting it to 20 September. Given these apparent discrepancies, the letter has been assigned a circa date.

While a fair copy of the letter was presumably sent, it is apparently not extant. ’s retained copy is featured here. There is no known response.