Help with Germanic & Scythian etymology

Greetings all,

I was looking back over a couple of myths regarding Germanic, Norse,
and eventually Scythian origins.... and thought perhaps someone here
could help me out a bit?

In Gmc myth the proto-ancestor is Tuisto/Tuisco, who then has a son
Mannus (man) who in turn has three sons: Ing, Irmin, and Istaev/Iscio.

Tuisto is generally believed to derive from *tvi- "two" , and thus to
have a name which reflects an androgynous nature similar to that of
Ymir (with who Tuisto shares some features).
Elsewhere some have put forth the idea that Tuisto is based on the
word for "conflict/dispute/division" which also springs from *tvi-
(German zwist, Swedish tvista, Dutch twisten)

Jakob Grimm suggested the name and variant forms (Thuisco, Thuiskon,
Tuisco) come from the adjective tivisco derived from the name of the
god Tiu; (from *Tîwaz), and the adjective derived from it could mean
either "celestial" or "son of Tiu".

My first question is whether anyone can shed any light on the
likelihood of one etymology versus another??

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The second matter is that of Mannus' son Istaev/Iscio - can anyone
offer an etymology to this?
(the name Irmin seems to mean "mighty/giant" , while Yngvi is a term
used in skaldic poetry to mean "king" and is another name for Frey)

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In the "History Of The Britons" (Historia Brittonum) by Nennius,
Mannus is referred to by the name "Alanus" - with his sons being
Hisicion, Armenon, and Neugio (to match Istaev/Iscio, Irmin, and Ing)
Lastly Tuisco seems to be replaced by a character named Fethuir.
Again, if anyone had any suggestions for ANY of the above individuals
it would mean a lot.

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A last possible correlate to the above matching tales, is that told
by Herodotus regarding the ancestry of the Scythians.
Here a man named Targitaus (a son of Jove) begat three sons,
Leipoxais, Arpoxais, and Colaxais.

Right after that Herodotus mentions the tale told by the Pontic
Greeks about the origin of the Scythians. In this story Hercules (son
of Zeus) begets three sons named Agathyrsus, Gelonus, Scythes.
In the two Scythian tales Colaxais and Scythes are equated but I
cannot determine the other brothers.


Tuisto = Fethuir = Jove = Zeus
Mannus = Alanus = Targitaus = Hercules
Istaev/Iscio = Hisicion =?
Irmin = Armenon =?
Ing = Neugio =?


I apologize for just throwing this out here, I know it is a bunch of
names, but I thought as they are all interconnected, it might be best
to put forth all the questions at once.

Sincerely,
Aydan