The to this question depends on which religion the Question has in mind. Of course it is only relevant to polytheistic religions, since there is no basis for the question if there is only one God or Ahura Mazda.
In the ancient Greek religion, the most important god was Zeus. In Rome, it was Jupiter, who was seen as equivalent to Zeus. Zeus was the sky god.
In Egypt, Ra was the most important god. Ra was the sun god.
In Hinduism, the Brahman trinity consists of Brahma, Vishnu and Shiva. Brahma was the Creator, but some say that Vishnu, the Preserver, is more important.
INDRA was the most important god of Aryans
the river god or the sun god were the most important gods to the egyptians
Indra or Purandhara was the most important God in the rigvedic period.
Zeus is the most important god
The hippos represent the god Taweret.
Dionysus provided the Greeks with a deity to represent alcohol, specifically wine.
Ra, the sun god
Ra,h is the god of creation
Brahma is the most important god in Hinduism
GOD.
The most important god was "Ra".
I think the most important gods to Aztecs are Sun god and rain god ( I said these two because they were important for growing crops) this was answered by NADINE