Like Adolf, right? 

I can handle the idea that people think Sadam or Hitler lived/escaped/went into exile.
However the ego it would require to rise to power, take control of a country, establish yourself as the sole leader, go on a war path instigating battle with neighboring nations and take command of them, turning on your allies and when the whole plan begins to unravel this individual would decide it would be in their best interest to retreat to some quiet, uneventful, relatively powerless, solitary life out of the public eye seems highly unlikely.
Personality changes can and do happen, it just seems far fetched that with these narcissistic type of individuals the change would be so drastic.