The Rigsthula is found in neither of the principal codices. The only manuscript containing it is the so-called Codex Wormanius, a manuscript of Snorri's Prose Edda. The poem appears on the last sheet of this manuscript, which unluckily is incomplete, and thus the end of the poem is lacking. In the Codex Wormanius itself the poem has no title, but a fragmentary parchment included with it calls the poem the Rigsthula. Some late paper manuscripts give it the title of Rigsmol.

The Rigsthula is essentially unlike anything else which editors have agreed to include in the so-called Edda. It is a definitely cultural poem, explaining, on a mythological basis, the origin of the different castes of early society: the thralls, the peasants, and the warriors. From the warriors, finally, springs one who is destined to become a king, and thus the whole poem is a song in praise of the royal estate. This fact in itself would suffice to indicate that the Rigsthula was not composed in Iceland, where for centuries kings were regarded with profound disapproval.

Not only does the Rigsthula praise royalty, but it has many of the earmarks of a poem composed in praise of a particular king. The manuscript breaks off at a most exasperating point, just as the connection between the mythical "Young Kon" (Konr ungr, konungr, "king"; but cf. stanza 44, note) and the monarch in question is about to be established. Owing to the character of the Norse settlements in Iceland, Ireland, and the western islands generally, search for a specific king leads back to either Norway or Denmark; despite the arguments advanced by Edzardi, Vigfusson, Powell, and others, it seems most improbable that such a poem should have been produced elsewhere than on the Continent, the region where Scandinavian royalty most flourished. Finnur Jonsson's claim for Norway, with Harald the Fair-Haired as the probable king in question, is much less impressive than Mogk's ingenious demonstration that the poem was in all probability composed in Denmark, in honor of either Gorm the Old or Harald Blue-Tooth. His proof is based chiefly on the evidence provided by stanza 49, and is summarized in the note to that stanza.

The poet, however, was certainly not a Dane, but probably a wandering Norse singer, who may have had a dozen homes, and who clearly had spent much time in some part of the western island world chiefly inhabited by Celts. The extent of Celtic influence on the Eddic poems in general is a matter of sharp dispute. Powell, for example, claims almost all the poems for the "Western Isles," and attributes nearly all their good qualities to Celtic influence. Without here attempting to enter into the details of the argument, it may be said that the weight of authoritative opinion, while clearly recognizing the marks of Celtic influence in the poems, is against this view; contact between the roving Norsemen of Norway and Iceland and the Celts of Ireland and the "Western Isles," and particularly the Orkneys, was so extensive as to make the presumption of an actual Celtic home for the poems seem quite unnecessary.

In the case of the Rigsthula the poet unquestionably had not only picked up bits of the Celtic speech (the name Rig itself is almost certainly of Celtic origin, and there are various other Celtic words employed), but also had caught something of the Celtic literary spirit. This explains the cultural nature of the poem, quite foreign to Norse poetry in general. On the other hand, the style as a whole is vigorously Norse, and thus the explanation that the poem was composed by an itinerant Norse poet who had lived for some time in the Celtic islands, and who was on a visit to the court of a Danish king, fits the ascertainable facts exceedingly well. As Christianity was introduced into Denmark around 960, the Rigsthula is not likely to have been composed much after that date, and probably belongs to the first half of the tenth century. Gorm the Old died about the year 935, and was succeeded by Harald Blue-Tooth, who died about 985.

The fourteenth (or late thirteenth) century annotator identifies Rig with Heimdall, but there is nothing in the poem itself, and very little anywhere else, to warrant this, and it seems likely that the poet had Othin, and not Heimdall, in mind, his purpose being to trace the origin of the royal estate to the chief of the gods. The evidence bearing on this identification is briefly summed up in the note on the introductory prose passage, but the question involves complex and baffling problems in mythology, and from very early times the status of Heimdall was unquestionably confusing to the Norse mind.