Genesis 15: 18 - 21: In the same day the LORD made a covenant with Abram, saying, Unto thy seed have I given this land, from the river of Egypt unto the great river, the river Euphrates: The Kenites, and the Kenizzites, and the Kadmonites, And the Hittites, and the Perizzites, and the Rephaims, And the Amorites, and the Canaanites, and the Girgashites, and the Jebusites.
Satan and his demons will come to their final end when they are consumed by the Lake of Fire (Revelation 20: 10); but until that time arrives, those demons have jumped from body to body throughout the course of history. A demon is a spirit that needs a body to inhabit for it to express itself; so when a demon-possessed person dies, the spirit that was upon that person will then look for another body to inhabit.
A classic example of this can be seen in Genesis 15 wherein God details ten nations that were opposed to Israel but which God promised Israel victory over.
The spirits that were upon those ten nations then came upon Haman’s ten sons (in the Book of Esther) who hated the Jews and likewise wanted their destruction. But after Haman’s ten sons were hanged, the spirits that were upon them entered into the Nazis (and many other characters in the pages of history), so that ten of these Nazis were hanged at the Nuremberg Trials of 1946 (see Haman’s ten sons).
Those spirits have since possessed the ten nations detailed in Psalm 83: 1 - 8 who at this very time are plotting and preparing for the destruction of modern Israel. And after these ten nations are destroyed, the spirits that are upon them will possess the ten horns (communist dictators) of Revelation 17; these ten horns will in vain attempt to make war with the Lamb before they are completely annihilated.