Christians, why do you think people once believed in Zeus and the greek gods?
Seriously, why did people create an entire pantheon of gods, with complete backstories, histories, personalities, and so on? What do you think inspired (for lack of a better word) them to do this? Why did they believe in these gods for well over 3,000 years? What were they looking for?
Now do the same for all god cultures: roman, hindu, etc.
Now answer me this...how does any of your answers to the above differ from your religion?