A comparison of the line of Danish kings as Saxo has it, with the line of the same kings in the Skjọldungasaga,[164] shows that the Skjọldungasaga has the story about Hroar and Helgi just where Saxo's second story about them (i.e., in his seventh book) puts in its appearance. These lines of kings are as follows:—

SAXO: SKJỌLDUNGASAGA:

Humblus I
Dan I
Humblus II
Lotherus
Scioldus Scioldus
Gram
Swibdagerus
Guthormus
Hadingus
Frotho I
Haldanus, Roe, Scatus
Roe, Helgo
Roluo Krage
Hiartwarus
Hotherus
Balderus
Roricus
Vigletus
Wermundus
Uffo
Dan II
Hugletus
Frotho II
Dan III
Fridleus I Fridleifus I[165]
Frotho III[166] Frotho I[166]
Herleifus
Havardus
Leifus
Herleifus[167]
Hunleifus[167]
Aleifus[167]
Oddleifus[167]
Geirleifus[167]
Gunnleifus[167]
Frotho II
Vermundus
Dan I
Dan II[168]
Hiarnus[169] Frotho III
Fridleus II[170] Fridleifus II
Frotho IV Frotho IV
Ingellus Ingjaldus, Halfdanus
Olauus[171]
Frotho V, Haraldus[172] Agnerus, Roericus, Roas or Roe, Helgo
Haraldus,[173] Haldanus,[174] Frotho (V)[175] Rolpho Krag

A comparison of the two lines of kings shows that, beginning with the first Fridleus in Saxo's account and the first Fridleifus in the Skjọldungasaga's account, there are important correspondences. Fridleus I (Saxo) = Fridleifus I (Skjs.). Frotho III, son of Fridleus I (Saxo) = Frotho I, son of Fridleifus I (Skjs.). Fridleus II, son of Frotho III (Saxo) = Fridleifus II, son of Frotho III (Skjs.). Frotho IV (Saxo) = Frotho IV (Skjs.); and in both sources Frotho IV is the Danish king in whose career Swerting plays such a prominent part. By omitting all of Saxo's kings between Scioldus and Fridleifus I, among whom are also the Hroar-Helgi group, the Skjọldungasaga has avoided the difficulty of having to deal with Hroar, Helgi, and Hrolf Kraki where they first occur in Saxo's history.

The paralleling of the two lines of kings also furnishes the key to the explanation of how the different names and a different setting for the Hroar-Helgi story, from those found in other versions, got into Saxo's version. Since the Hroar-Helgi story appears in the same place in his line of kings as in that of the Skjọldungasaga, he must also have known the names that really belonged to the story. But he had told the story about Halfdan, Hroar, Helgi, and Hrolf Kraki (in its second stage of development, see p. 66) once before, and therefore could not consistently tell a different story about the same men. The story was, however, in existence and was too good to be discarded, so he retained it, but disguised it by making arbitrary changes. This explains the loss, which otherwise would be very strange, of such well known names as Hroar, Helgi, and Hrolf Kraki. The only incentive any one could have to change the names would be just that which Saxo had, namely that he had used them before in another connection. He retained the name Frothi, which appears so often in the Danish line of kings that its reappearance would cause no difficulty; and his retention of Frothi as the slayer of his brother is additional evidence that to him, not to Ingjald, was this unenviable rôle first assigned. Ingjald, whom he has in his story about Hrolf Kraki, he also retained, but in a different relationship from that in his second book. It will be observed that Saxo merely shifted the name Halfdan from father to son, and that Harald, almost a conventional name, he employed twice. Finally, he introduced a strange person, Olaf, about whom, he says, nothing, practically, was known.

But since Saxo has the Hroar-Helgi story substantially as it is in the Hrólfssaga, except for the changed names, the author of the Skjọldungasaga, or its source, whose version of the story occurs in the same place in the line of Danish kings as Saxo's, must also have known the story in the same version. This we shall find was actually the case, and that the story as it appears in the Skjọldungasaga is an attempt at reconciling conflicting elements in ancient tradition.

As already stated, according to the Grottasọngr (from about 950), Frothi is the brother of Halfdan and slays him. But according to an equally old tradition, the story on which the Ingjald lay in Saxo's sixth book is based, Frothi is Ingjald's father and is himself slain. The events that gave rise to this lay are also narrated in Saxo's sixth book and are as follows.

In Saxony were two kings, both of whom paid tribute to Frothi. They planned to throw off the foreign yoke. Hanef made the attempt first, but Frothi defeated and slew him. Swerting made the attempt later and slew Frothi, but met his own death at the same time. Swerting's sons, fearing that Ingjald would avenge his father's death, gave him their sister in marriage. Thus a reconciliation was effected, and Ingjald thenceforth devoted himself to pleasure. Starkad, the famous warrior, who was in Sweden, had been one of Frothi's men and had later been Ingjald's foster-father. When Starkad learned that Ingjald, instead of seeking revenge, had made friends with his enemies and had taken Swerting's daughter to wife and with her was leading a life of luxury, the old warrior hastened back to Denmark. When Starkad returned, Ingjald's wife, not knowing him on account of his shabby appearance, insulted him. Ingjald was away on a hunt at the time; but when he returned, he recognized Starkad and told his wife who the old man was. In the evening Ingjald sat down to a luxurious meal with Swerting's sons; and his wife did all she could to appease Starkad, who was also present. But Starkad could not forget the insult he had suffered, and became more and more angry with the effeminate way of living that Ingjald and his wife had introduced from Germany. In burning words, which are reproduced in the Ingjald lay, he condemned Ingjald's neglect of duty, his luxurious mode of life, and his living in friendship with those on whom he should have avenged his father's death. Ingjald was finally aroused, and he drew his sword and killed all of Swerting's sons. In regard to his future relation to his wife Saxo says nothing; but as Starkad advised him to drive the impudent woman (as he called her) from the land, the presumption is that Ingjald did so.

The Ingjald lay has its roots in Beowulf. Its relationship to the corresponding episode in the Anglo-Saxon poem is explained in the following by Olrik:—

"Kun et eneste af Starkad-digtningens mange optrin kan fölges til ældre kilde end de nordiske. Det er den scene, hvor den gamle kriger opægger Ingjald til hævn og dermed afbryder forsoningen imellem de to fjendtlige slægter. I Béowulf findes dette optrin for förste gang, ganske afvigende i den politiske stilling, men med kendeligt slægtskab i det digterske indhold.