Babylon, Gog, and King of the North

Please kindly explain Gog of Magog, King of the North and Babylon the great. Do they all mean the same thing? There are subtle differences, but similarities. Two of the entities have been around a long time, since before the time of Christ; that being the king of the north and Babylon the Great. Gog of Magog comes on the scene in the final part of [...]