The Asvins/Dioskouri

The Horse Twins - the Dioskouri - associated with night (death) and
day (immortality) appear as twin horses, bearers of the chariot of
the light of the sun. Given that we find them in some way
associated with the origins of Humanity in Indo-Aryan myths - (Manu
and Yima/Hindu Yama) and with Kingship everywhere (Horse burials
seem associated with this particular mythos - where the dead horse
accompanies his master into the afterlife, and his "twin, resumes
the throne).

Clearly this would seem to be associated with the idea of the spoked
chariot and the war-leader tanist idea. Since this form of warfare
only came about in the period after 2,000 BCE it is hardly universal
within PIE, yet we find Ymir in Germanic Myth and Tanists and horse
burials in Irish legends.

Can anyone cast some "light" on when the "solar chariot" appeared in
Indo-European mythology?

Regards

John