Had Stalin lived 10 years longer, I believe that the Soviet Union would have collapsed very rapidly after his death.

Had the French retained Canada after the Seven years War, a number of things would have followed that would have had a significant impact on that side of the "pond". There would have been no War of Independence and there would have been no expansion by the "colonists" westward into the Ohio and Wabash Basins, Britains fledgling colonies on the eastern seaboard of America were hemmed in by French and Spanish possessions, and it would have they who would have "Won the West" - a thing I suppose the natives would have been much happier with.

Points made regarding what would have happened if Germany had won the First World War rather fancifully allows France retention of her overseas possessions. Now I say fancifully as IIRC Kaiser Bill at one point or other prior to the totally pointless stramash that became known as the "Great War" was known to have wittered on about Germany "winning her place in the sun". In the wake of a German victory France would have lost her colonies to France and that would have set Germany on a collision course with Great Britain.

While the thinking behind the treaty of Versailles was seriously flawed (at the insistance of Clemanceau) Hitler would have been stopped dead in his tracks if he had been confronted the second that Germany started to break and ignore the conditions of the treaty that they had signed.