Allegedly he was Lucifer, most beautiful of the angels, who got a bit fed up with all the adoring of God and so on and was part of the Angelic Rebellion.They lost God cast him down like the benificent entity he turned out to be... (plagues, famines, dead first borns, frogs etc).
The Question should really be.... "Did God create Satan and ,if so, for what purpose " ? Bearing in mind that the existence of God has never been proved.
beso is asking the question of those who believe the Creation story.
It's another of those peculiarities like having been the son of Adam and Eve (first people on earth, remember) 'whom', exactly, did Cain find to marry when he was exiled to the Land of Nod?
There was an American motorcycle gang who decided to call themselves Satan's Angels and wanted this tattooed on their arms. It was only after the last one was finished did they realise they had become Stan's Angels.
I am surely not the only one who thinks that it is odd that Satan is an anagram of Santa. Santa, as we all know, really does exist. All the rest is bovine excrement.