Did Sir Walter Scott really revivify the past in his poems and romances? No, he stopped short on the threshold, preferring that which would interest to that which was true. Had he painted the past as he knew it to have been, the picture would have shocked the majority of his readers. He dared not draw either the voluptuous enthusiasts of the Revival, or the heroic brutes and ferocious beasts of the Middle Ages. His real glory lay in throwing a poetical and unfading halo over his native land, in making Scotland forever attractive to mankind.How to rescue Scott from the land that some contemporary international fans (apparently) thought has been named after him?
One might be to return to the wordage itself: the textuality of Scott’s ‘halo’. Robert C Gordon's Under Which King? A Study of the Scottish Waverley Novels (1969), whilst not dealing with Scott's poems, does have some interesting things to say about Scott's affinity to Byron.
Sir Walter Scott was a great novelist with a weak aesthetic conscience. He never entirely escaped from a conviction that writing was a scribblers trade, unworthy of the landed gentleman or the man of business. The magnificence of his successes was a virtue achieved by a powerful imagination working upstream against a current of doubt and prejudice that would have defeated a lesser talent. He once praised Byron, in words that chill, for achieving literary fame whilst "managing his pen with the careless and negligent ease of a man of quality" [MPW iv.375]. It was a justification of literary Whiggery by an appeal to aristocratic principle, a characteristic compliment. Byron cast no halo on his native land; indeed, the dissipation of halos (and dissipation more generally) is kind of the point of Byron. Scott’s poetry is resolutely moral, of course, especially by comparison; but there seems to me something going on in his epic-y narratives. They dissipate.
Herbert F. Tucker has written an enormous book on epic and long poetry of the Romantic and Victorian periods, called Epic: Britain's Heroic Muse 1790-1910 (Oxford University Press 2008). On The Lay of the Last Minstrel, Tucker covers a lot of ground quite quickly:
The Lay skirted epic borders. This would have been instantly apparent to readers whose sharp memory of the Ossian controversy was kept fresh by editions of balladry, themselves controversial ... from revised versions of Percy's Reliques to Joseph Ritson's Ancient Songs (1790) and subsequent collections to Scott's own Minstrelsy of the Scottish Border (180203), which would reach a third edition by 1806. George Ellis's thorough scholarship in Specimens of Early English Metrical Romances, published the same year as The Lay, set Scott's chosen genre on a continuum running from trouveur balladry through 'something like an epic fable' in the 'ruder hands' of the Normans, to the Italian refinement of 'a new and splendid species of epic poetry.' Among contemporary poets, Wordsworth and Coleridge had adapted these forms with epoch-making originality in Lyrical Ballads (1798) and the unpublished but circulating 'Christabel'. [121-22]Tucker goes on to argue that the Lay's success lay in 'foregrounding narrative as performance':
Neither the central-casting Minstrel, not the Duchess who favours the entertainment is memorably drawn; and it is plan from the kindly intercalations of the Duchess and her ladies that even they do not value the story he offers them much more highly than the dispassionate modern reader can. Yet all this scarcely matters. The secret of the poem's success lay elsewhere: in the means of its transmission, in the ingenious modulation of new-old verse and in the presentation of the narrative frame as itself a text in motion, ie a narrative possessing independent value. ... For [contemporary epic poets] Cumberland, Blake, Southey and the rest the relation of past to present remained serenely unproblematic, Not so, however, for Scott or, to judge from the enthusiasm The Lay excited, for the reading public either. History was a problem, not just a resource. With unobtrusive genius Scott both acknowledged the problem abd proposed to solve it through the continuity-therapy that a sympathetic writer and reader might conspire to effect. [123-4]This 'continuity-therapy', I think, has to do with the way Scott gives weight to both the present-day framing device and the historical tale, and does so in a way that engages and involves his readership. But Tucker thinks Marmion is an even greater achievement.
This poem of 1808 was an epic transaction that brilliantly infused into the entertaining sophistication of the Lay a tone and an ethos addressing the national trouble that contemporary epics of a more turgid sort had begun churning up. Instructed perhaps by [Southey's] Madoc, which he read more than once, Scott showed in Marmion how heroes' guilt and victims' history might conspire to support a narrative economy of loss and gain; and he suggested how a reader's speculative investment in such a narrative economy might redound to the national interest. He did so by correlating the breaking and keeping of faith, at several stuctural levels, with the maintenance of continuity between past and present on which personal identity and British history alike depended; and by infusing into the narrated flow of heroic psychology the epochal theme of historical change which The Lay of the Last Minstrel had been content merely to stage. Tucker's reading of Marmion is a dozen dense-pages long, and I can't do justice to it here. His main argument is that Scott uses medieval history as a way of writing about Modernity, paradoxical as that sounds: 'Modernity is a chronically recurrent condition, one that sustains itself by running back to an origin it discernibly yet incompletely differs from. harbouring the incompleteness of that difference as guilt -- accepted because shared, and carried forward because perennially unpaid -- is the work of national history as Scott momentously defined it for the nineteenth-century. And he taught the world how to do this work in the novel only after undertaking it first in epic poetry, the literary genre with which national history was most firmly associated in his lifetime.'  Tucker doesn't have much time for the other Scott long poems, though.
In The Lady of the Lake (1810) and Rokeby (1813) Scott untwined for separate consideration historical factors that the epic web of Marmion had woven together: in the former, the conflict between waning and emerging cultural formations, represented in figures who are nearly allegories of thsoe formations; in the latter, the narrative burden of guilt as it fastens on, and bends inward into personhood, figures enmeshed in the density of national events, the latter now further complicated by New World buccaneering. Scott's decline hereafter through perfunctory self-imitation in The Bridal of Triermain (1813) and The Lord of the Isles (1815), towards the outright parody of Harold the Dauntless: a Poem in Six Cantos (1817) confirms that by mid-decade he had designated Byron his heir in metrical romance and was saving himself for prose fiction. Harold is pretty weak, I agree; but this seems to me hard on both Triermain and Lord of the Isles, both pretty interesting poems in various ways, I think. But the broader point, that these poems 'about' history are actually about the dissipation of history, is very interesting.