In some Greek myths he is depicted as the deity of the sun, e.g. the myth where his son, Phaethon, takes his chariot for a ride. Yet Homor does not refer to him at all as a solar deity.
If Helios was a/the solar deity, then how was Apollo ever connected to the sun?
Where did this connection come from, and how did it change over time? ( And what did the Romans do when they adopted Apollo in there own pantheon?)
Apollo was known to ride the chariot as to pull the sun across the sky. Eventually, more and more greek gods were either forgotten or were combined into one entity EG Apollo and Helios being just Apollo as many people of modern times assume they were one and the same.