You could upload the map as an image, either tagged to individual family member profiles or a new free-space page where you tell the migration stories.
You can't actually embed a map, or even an image for that matter, inside the text of a page. That's a limitation we placed on the system. (It reduces spam and vandalism risks. Though, now that I think about it, neither has been a problem since we went invitation-only. We could probably go back to allowing it.)
Maybe others have specific suggestions or ideas.