Egil, an archer in Heaven
The lid was composed of three side-to-side bone segments, only the middle one of which has survived. As the outer edges of it do not bear any runes and as the carving did not extend beyond the upper and lower border there will never have been an inscription. The missing segments will have been plain and covered with silver fittings. The rune master may have shrunk from commenting on the realm of the fierce god - a taboo, so to say - just as he had already encoded his words on the realm of death.
Though this panel is only a part of the once-lid, it seems as if it is the complete picture. It covers the entire breadth of the casket, so we can be sure that there was no inscription at all. To the top and bottom there is a clear borderline. If the plain bone plate framing the picture had been covered with rolled silver, it may have been decorated with silver shields, rendering the roof of Valhall.
So there is just the word Ægili1, the name of a once famous archer who in the course of saga tradition eventually became a Wayland brother, - may be as early as here. There is no myth of him in Valhall reported. The god Ull2 would have been a perfect archer instead, but the rune master needed the rune (standing for resistance), which may have helped Egil to his unexpected apotheosis as Ægili.
Though his origin is uncertain it is unlikely that he should be identical with Achilles, the Greek hero, who himself fell victim to an arrow. It looks as if the similarity of the rune with the Greek letter chi had inspired the interpretation.The i-auslaut (in final position) is unusual, but does not indicate some genitive form, it is rather put for numeric reasons.
If in the literature3 reference is made to the Greek Heros Achilles, which can be appropriate from the point of view of sound change, then the contextual justification is missing. This however results from our interpretation ( Æ - panel (The Lid) - The Pleiades and the Cycle of the Year), according to which this archer Egil symbolizes the summer constellation (sic!) "Sagittarius". In traditional zodiac depictions, the centaur Cheiron stands here, who taught the young Achilles the archery.
1 Egil is a legendary hero of the Völundarkviða and the Thidreks saga. The name is from Proto-Germanic *Agilaz, and the same legend is reflected in Anglo-Saxon Ægil of the Franks Casket and Alamannic Aigil of the Pforzen buckle.
The Proto-Germanic form of the legend may only be guessed at, but it appears likely that Egil was a renowned archer who defended a keep together with his wife Aliruna, against numerous attackers. The testimony of the Pforzen buckle is uncertain beyond naming Aigil and Ailrun, possibly adding that they fought a battle at the Ilz river. The Franks Casket shows the scene of Aegil and his wife enclosed in the keep, with Aegil shooting arrows against attacking troops.
In the Völundarkviða, Egil is a son of a Finn king, his elder brother being Slagfinn, his younger one Völund. The three brothers marry valkyries they encounter in swans' form, Slagfinn marries Hladgud, and Völund marries Hervör, daughters of king Hlödver, while Egil marries Ölrún, a daughter of the Roman Emperor (Kiár of Valland).
In the Thidreks saga, Egil acts as a masterly archer, once he is forced by king Nidung to shoot an apple from the head of his son. He readies two arrows, but succeeds with the first one. Asked by the king what the second arrow was for, he said that had he killed his son with his first arrow, he would have shot the king with the second one. This tale is directly comparable to the legends of William Tell and Palnetoke. As opposed to Tell's case, the king doesn't try to punish Egil for his openness, but, to the contrary, commends him for it (chapter 128). Völund is crippled by Nidung and held captive at his court. To help his brother, Egil shoots birds and collects their feathers, of which Völund makes a pair of wings. Völund ties a bladder filled with blood around his waist and flies away. Nidung commands Egil to shoot his fleeing brother, who hits the bladder, deceiving Nidung, and so Völund gets away (chapter 135).
2 Ullr appears in Germanic paganism to have been a major god in prehistoric times, or even an epitheton (*wulþuz, Old English wuldor, meaning "glory") of the head of the Proto-Germanic pantheon. Ullr is mentioned on the 3rd century Thorsberg chape and in late Icelandic sources but not much other information regarding the god has survived.
The Prose Edda
In chapter 31 of Gylfaginning in the Prose Edda, written in the 13th century by Snorri Sturluson, Ullr is referred to as a son of Sif and a stepson of the major Germanic god Thor: "Ullr heitir einn, sonr Sifjar, stjúpsonr Þórs. Hann er bogmaðr svá góðr ok skíðfœrr svá at engi má við hann keppask. Hann er ok fagr álitum ok hefir hermanns atgervi. Á hann er ok gott at heita í einvígi."
Ull, Sif's son and Thór's stepson, is one [too]. He is such a good archer and ski-runner that no one can rival him. He is beautiful to look at as well and he has all the characteristics of a warrior. It is also good to call on him in duels. — Young's translation
In Skáldskaparmál, the second part of the Prose Edda, Snorri mentions Ullr again in a discussion of kennings. Snorri informs his readers that Ullr can be called ski-god, bow-god, hunting-god and shield-god. In turn a shield can be called Ullr's ship. Despite these tantalising tidbits Snorri relates no myths about Ullr. It seems likely that he didn't know any, the god having faded from memory.
3 Karl Schneider, Festschrift Fischer, p. 6 f