Satan was born a child of privilege, and he grew up as an angel in God's court. He was wealthy and spoiled, and from as soon as he could talk he was embroiled in the palace intrigues. As a young man he was a rebel, a mover and a shaker. You should have known him then. But then his rebelliousness went too far, and he tried actual rebellion. The coup de tat failed, and he was stripped of his angel status in a formal ceremony. Everybody was there. And he was tossed out of heaven. Literally. In those days they took you to the outer wall and threw you over it.
The fall went on for years, and it burned Satan into a figure of tattered black by the time he came down through the sky of hell like a meteor and crashed in the desert, blowing a crater in the dirt. Months passed while he lay and cursed his immortality. Eventually, decades later, he recovered enough to sit up. He could tell he wasn't the first. There were other impact craters scattered across the landscape.
Through the murky atmosphere he could make out the sparks of distant fires. He stumbled toward them, and discovered he was in the bullseye of a vast camp of outcasts. He joined them, and he thrived in hell, making his way as a thief at first, and later through extortion and drug dealing. He rose to leadership of a gang because he was lucky and clever, and that's when-- one night, lying in his bathtub-- he had his great vision. He realized that if he couldn't rule heaven, he could rule hell.
He built coalitions, gathered weapons, and launched an all-out assault on the bastions of the rich and powerful, the towers on the hieghts of the devils who ruled hell. The battle went badly, and Satan's army was crushed. But he was no longer there. He was coming in the back way at the head of second army, an overwhelming assault force.
Immediately after the victory celebration, his administration dissolved into civil war. Satan maneuvered things so that he was the leader of the faction that eventually won, and then he settled down to ruling hell. By now he was known as, "Godfather."
Like all bureaucracies, his was 10% efficient at it's stated task, and 90% efficient at its own survival. Satan began a massive purge, lasting centuries, and succeeded in tightening things up to 22% efficiency. Then his minions stormed the ramparts of heaven. He'd decided he might as well fulfill his original dream and rule heaven, too.
The angels in their bunkers ran computer simulations, and discovered that resisting the assault opened an avenue of corruptability that led straight to them. By the time they could open negotiations, Satan's hordes had already taken over the heavenly suburbs.
The settlement negotiated in the end was that heaven had to pay for installing some infrastructure in hell, things like plumbing and electricity, and Satan's army gave back the suburbs. The agreement also gave Satan the right to run for the job of God in the next election, and through a massive advertising campaign funded with drug monoey, along with some dirty tricks, he won.
The day Satan moved into his new office was the happiest of his life, and he threw a party for his cronies that lasted for weeks. He had some interesting and disturbing new ideas for his administration, but he could hardly get started before he was distracted by the troubles of the office. Angels were rioting in the streets in protest of his victory, the plumber's union walked out on their contract, the city council was screaming for better security measures... it went on and on. And then hell erupted in revolt, just to top it off. It seems some young punk named Lucifer had taken over.
Here's a version of Satan you can download: