I do not know how this can be answered in detail, but I'll give you this.
The ancient peoples developed organized agriculture and primative religions to bolster their yield (plant by full moon, watch for solstice, etc.). They thought about the "wanderers", were the stars fixed to the vault of heaven, what was beneath the flat earth. They built on these ideas in every major culture East and West. They gave names of importance to these special objects.
(Aristotle decided in favor of, and then rejected the motion of the Earth. A century later, Aristarchus made his own study, and accepted the Earth circled the sun, but underestimated the distance to the stars, saying they were not far beyond the planets. The clout of the greeks held sway.)
As time proceeded, Egypt and the muslim world came and went, as did Greece, and then Rome, but Rome absorbed many greek gods. The fall of the Roman Empire gave way to the Dark Ages. What arose after that involved the humanism of the Renaissance, which actually began with tourism to ancient Greece. The Italians uncovered forgotten greek sources of classical knowledge. I think that helped kick off the Renaissance.
The gradual acceptance and improvement of scholarly pursuits, made Europe the center
of astronomy (optics, telescopes). Their naming of new stars, constellations, and later nebulas and galaxies went into the accepted maps, made by the accepted experts. During this time, a background "in greek and roman classics" was considered the norm for someone of learning.
There are odd names that people invented when mythological figures ran short- Microscopium...
But, as to the specific names of the planets, the gods surely were interested in those celestial bodies- they were "special". And who was to know different? Who wanted to take a chance? Religion did get crazy, at times, though... But, ancient astronomy goes hand in hand with survival, religion, and so forth.
As an aside, I remember this story-
http://news.bbc.co.uk/1/hi/world/americas/4767717.stm