This topic is a response to a Too Human Norse Mythology topic that strayed from gaming to religion.

A Short History of Christianity, from Polytheism to Monotheism and back to Polytheism

When Hebrews created Judiasm, they borrowed many aspects of their religion from older religions of their surrounding cultures.  They mainly borrowed ideas from the Bablyonians, most importantly the story of Creation and Noah's Flood.

The story of Genesis was heavily influenced by Bablyonian religion and the creation story Enuma Elish (full text link below).  In the Enuma Elish, Marduk becomes the king of the gods, defeats evil gods, and then created Earth in the same order as Genesis and has a feast on the 7th day.  The Bible and Enuma Elish description of Earth are exactly with the same, with the Earth being a flat disk with a firmament full of stars extending from the ends of the Earth to the Heavens.

The story of Noah's Flood is directly influenced by the Bablyonian Epic of Gilgamesh.  Many other cultures also have flood stories, which probably has something to do with the end of the ice age and the huge rise in sea level.

Examples of the Bible's influence from Bablyonian mythology are when God creates "man in our image" He is referring to Marduk creating man in the image of the gods.  The battle between God and Satan and Gods victory was borrowed from Marduks victory over the rebellious Bablyonian gods.  Also, the reason Marduk created man was for the gods to rest as men ruled over the Earth in their place, similar to God creating man and giving him dominion over Earth.

Then God said, "Let us make man in our image, in our likeness, and let them rule over the fish of the sea and the birds of the air, over the livestock, over all the earth, and over all the creatures that move along the ground." - Genesis 1:26

Thousands of years after the creation of Judaism, Christianity split from tradition with the belief that God had a son.  The idea of multiple gods didnt set will with Jews, but it was easily picked up by Pagan Romans who, at that time, had no problems with gods having children nor did they have problems with gods walking the Earth in human form (the Romans thought the Emperor was a god).  Constantine adopted Christianity in an attempt to culturally unite a weakening, dividing Roman Empire.  However, as historians have argued, the Romans became preoccupied with religion and preparing for the afterlife and less worried about their current military and economic state on Earth, speeding up their downfall.  The Romans were overran by Pagans from the north, which brings us to my next point.

When the Pagans adopted Christianity they brought their Pagan traditions with them.  Easter from the Jewish Passover, is symbolized by bunnies and eggs, representing the Spring equinox and the fertility it brings with it.  Chirstmas falls on the Winter Solistice, the Pagans actually had no idea when Jesus was born (from Roman tax records it is believed Jesus was born in the fall), but they brought the celebration of the Winter Solistice with them when they converted to Christianity.  Haloween is primarily Pagan with little or no transition it to Christianity.

So, when you are wondering where you current religion comes from, you should look past your own religious texts and read texts that your religion borrowed from.  In the case of Christianity, you should also look into Babylonian, Egyptian, Roman, and Greek mythologies as well as our beloved Norse Mythologies (with Odin and the concept of Hell).

http://www.crivoice.org/enumaelish.html

there is only zuul

"However, as historians have argued, the Romans became preoccupied with religion and preparing for the afterlife and less worried about their current military and economic state on Earth, speeding up their downfall"

What? Rome was "downfalling" way before Christianity became the state´s religion.
And obviously many religions are going to have things in common.

We´re humans. The images we use, the metaphors we create are always going to be similar, because we share similar functions (we think alike). That´s what makes society possible for us. It´s not a simple rip-off.

The fall of the Roman Empire generally leads to Constantine. Not only did he move Rome's capital to Constaninople but he allowed Christianity to become the dominant religion.

After Christianity became the dominant religion, Romans were more concerned with religion and the afterlife than governing their empire. They started hiring more and more barbarian mercenaries to fight for them, who often ended up turning on the Romans creating more problems. As their borders were weakening and their economy started to collapse, the Germans started moving in, and a mere 200 years after Constatine the (Western) Roman Empire had fallen.

Anyone who thinks ANY religion was created in a cultural vacuum is severely misguided. Religions love stealing from each other. It doesn't necessarily mean that those religions are inherently flawed, it just means you have to look at them in a broader context.

I gave up religion and started thinking for myself about 5 years ago. Not to talk down to the religious people but i prefer to come to my own answers and not trust the words of a text that was change by it's respective church since it was written over a thousand years ago.