Much of the story of the Russian empire, Germany's unification, WW1, WW2 and even today's war in Ukraine can be told by dragging this timeline from 1000 to modern day and focusing on Poland.
The east/west lines of Poland from 1029-1569 roughly correspond to today's east/west lines. But between now and then Poland shifts east then back west. Only after a ton of wars and death:
1. Poland basically expands massively to become Poland-Lithuania
2. Poland-Lithuania gets eaten by Germany (Prussia) to the west and Russia to the east.
3. Poland reappears, but entirely shifted east in the 1800s
4. Poland gets eaten by Russia again
5. Poland reappears after WW1
6. Poland gets eaten by Germany and Russia again in WW2
7. Poland shifts back west by Stalin and his mass population transfer program. Back almost to the original east-west borders of medieval Poland.
This is obviously a simplification of a 1000 years of history.
The east/west lines of Poland from 1029-1569 roughly correspond to today's east/west lines. But between now and then Poland shifts east then back west. Only after a ton of wars and death:
1. Poland basically expands massively to become Poland-Lithuania
2. Poland-Lithuania gets eaten by Germany (Prussia) to the west and Russia to the east.
3. Poland reappears, but entirely shifted east in the 1800s
4. Poland gets eaten by Russia again
5. Poland reappears after WW1
6. Poland gets eaten by Germany and Russia again in WW2
7. Poland shifts back west by Stalin and his mass population transfer program. Back almost to the original east-west borders of medieval Poland.
This is obviously a simplification of a 1000 years of history.