Forever Red Alert 1

More Information
Red Alert 1 contains some very innovative story board , telling about an alternative time line in which Stalin is trying to take over the world , after Einstein and his Chronosphere cancelled the possibility of germany starting world war 2. Your task is to help stalin take over the world , or help the allies forces defend it.
Some more detailed explanation can be found in wikipedia. Also you can read about the idea of the cronosphere and cronoshift in there.