The draft of The Devil's Walk in Shelley's mid-January 1812 letter to Elizabeth Hitchener of mid-Jan. 1812 (which we transcribe diplomatically as a Supplement to the published version) is far from a finished poem. But by August 1812, Shelley had prepared for distribution a fully developed satirical poem of 30 stanzas and had it printed as a broadsheet (arranged in three columns of ten stanzas apiece) entitled The Devil's Walk, A Ballad. This poem treats several topics that are absent from his draft in the January letter--some of more recent date. We know that Shelley's diabolical ballad was printed after he left Ireland on 4 April 1812, because it was not seized by the customs agent at Holyhead along with the Declaration of Rights (DR; for this seizure, see E. B. Murray in Prose I, 349). Shelley thus did not complete the poem or, probably, write his attack on the Prince Regent in lines 67-79 until after Leigh Hunt and his brother John were charged with seditious libel for publishing a critique of the Prince in the Examiner for 22 March 1812 that called him "a corpulent gentleman of fifty," besides alluding to his flaws in character. Shelley seconds and extends their attack by calling the Regent a fat-head as well as an obese glutton, but given the Hunts' legal difficulties, Shelley probably did not decide to print or circulate The Devil's Walk to challenge the government until after July 1812, when the ministry postponed the Hunts' scheduled trial for fear that a regular jury might not convict them (A. Blainey, Immortal Boy . . . Leigh Hunt, 54-6).
After the Shelleys crossed from Ireland to Holyhead, they proceeded to Nantgwillt, near Rhayader, Radnorshire (now Powys) by ca. 16 April, and stayed at the estate of Shelley's cousin John Grove at Cwm Elan through mid-June, before proceeding to Devonshire by way of Chepstow at the foot of the Wye Valley; they arrived at Lymouth (now Lynmouth), Devon, between 25 and 30 June (see E. Dowden, Life of Percy Bysshe Shelley I, 266-279 and Letters I, 280-310). The facts of Shelley's excursion into Devon are examined cogently, with extended quotations from relevant documents, by F. D. Mac-Carthy in The Early Life of Percy Bysshe Shelley (321-53); R. Holmes best captures the human drama in Shelley: The Pursuit (133-62), and K. N. Cameron explores its political implications in Young Shelley (165-86). In April 1812, Cobbett's Political Register reported that there were food strikes and other popular disturbances in Cornwall and parts of Devon, including Barnstaple (Young Shelley 175-78). Since Shelley regularly read Cobbett's periodical, he probably went to Devon with the idea of stirring those warm ashes, for from the time that he left Keswick, Shelley had elected to play the role of outside agitator, hurrying to sites of discontent, first Dublin and then to Devon, to try to redirect the course of those anti-government feelings. These activities earned him the serious attention of the local authorities.
The context of these political aims helps explain why Shelley should release two more "popular" works in Devon--The Devil's Walk, aimed at the lower classes, and Declaration of Rights, calibrated for the bourgeoisie--so soon after the failure of his similar efforts in Dublin, where he found that the Irish nationalists did not trust a very young Englishman. The food riots in Devon also provided part of his motivation for satirizing the Prince Regent's gluttony. Though Shelley opposed violence as a means of redress on both moral and pragmatic grounds, his theory was to move the discontented people to seek reform by using rational and moral suasion. But since his experience in Dublin made him (like Coleridge and Southey before him) doubt that the common people were well equipped for intellectual and moral conflict, he appealed to them in The Devil's Walk (as later in The Mask of Anarchy) in doggerel verse-satire based on popular religious symbols. For an analysis of The Devil's Walk in the context of Shelley's ambivalent feelings toward the whole genre of satire, see S. E. Jones, Shelley's Satire (1994), 38-48.