explaining his connection
with Annwfn in a different way from the account in the _Mabinogi_. The
poem also tells how Gweir was imprisoned in Caer Sidi (=Annwfn) "through
the messenger of Pwyll and Pryderi."[400] They are thus lords of Annwfn,
whose swine Gweir (Gwydion) tries to steal. Elsewhere Caer Sidi is
associated with Manawyddan and Pryderi, perhaps a reference to their
connection as father and son.[401] Thus Pryderi and Pwyll belong to the
bright Elysium, and may once have been gods of fertility associated with
the under-earth region, which was by no means a world of darkness.
Whatever be the meaning of the death of Pryderi at the hands of Gwydion,
it is connected with later references to his grave.[402]

A fourth group is that of Beli and his sons, referred to in the
_Mabinogi_ of Branwen, where one of them, Caswallawn, usurps the throne,
and thus makes Manawyddan, like MacGregor, landless. In the _Dream of
Maxen_, the sons of Beli are Lludd, Caswallawn, Nynnyaw, and
Llevelys.[403] Geoffrey calls Beli Heli, and speaks of an earlier king
Belinus, at enmity with his brother Brennius.[404] But probably Beli or
Heli and Belinus are one and the same, and both represent the earlier
god Belenos. Caswellawn becomes Cassivellaunus, opponent of Caesar, but
in the _Mabinogi_ he is hostile to the race of Llyr, and this may be
connected with whatever underlies Geoffrey's account of the hostility of
Belinus and Brennius (=Bran, son of Llyr), perhaps, like the enmity of
the race of D[^o]n to Pryderi, a reminiscence of the strife of rival
tribes or of Goidel and Brython.[405] As has been seen, the evidence for
regarding Beli as D[^o]n's consort or the equivalent of Bile is slender.
Nor, if he is Belenos, the equivalent of Apollo, is he in any sense a
"dark" god. He is regarded as a victorious champion, preserver of his
"honey isle" and of the stability of his kingdom, in a _Taliesin_ poem
and in the _Triads_.[406]

The personality of Casswallawn is lost in that of the historic
Cassivellaunus, but in a reference to him in the _Triads_ where, with
Caradawc and Gweirydd, he bears the title "war king," we may see a
glimpse of his divine character, that of a god of war, invisibly leading
on armies to battle, and as such embodied in great chiefs who bore his
name.[407] Nynnyaw appears in Geoffrey's pages as Nennius, who dies of
wounds inflicted by Caesar, to the great grief of Cassivellaunus.[408]

The theory that Lludd Llaw Erein