Lucifer was God highest ranking angel and leader in the worship of God, but Lucifer wanted to be God, he tried to fight God and he was thrown down to hell by God’s one of God’s angels, Gabriel. Lucifer had many followers in heaven and many followed him to hell. He later tempts Adam and Eve creating human sin, giving him some domain over earth. Later in history there was a period where the fallen angels reproduced with human women creating the demonic spawn that usually does his bidding. He was later called Satan deeming he was no longer worthy of the name Lucifer and was changed to Satan or the Devil. Just as God changed Abrams name to Abraham in the Old Testament.