I have a question. What's the current population of the territory formerly part of Germany, which is not part of Poland?
The Kaliningrad Oblast has a population of about a million, half of which lives in Kalinigrad city. Memelland has about 150.000 people. But this number has nothing to do with the original population numbers, it is solely the result of Russian and Lithuanian colonization.
And the territory east of the Curzon Line no longer part of Poland? I've looked online but can't find that info.
IIRC about 3,5 mln Poles lived east of the Curzon Line in 1939 if not more, as about a million were killed by Soviets during the war, and another 2 million were expelled after the war, the present Polish population in Lithuania, Belarus, Ukraine and Russia is over a million
I'm looking to track the population development of Poland after ww2 if they had kept the Curzon line.
Uh, they didn't "keep" the Curzon Line after ww2 - it was forced on them. Not sure what you mean here - if you mean no population transfers, then western Poland may be slightly less densly populated, but not much as it would still be populated by remaining Poles from central Poland (most of the Polish population were peasants living on
very small farms, if less of them move west, they get larger pieces of land, as do those left behind). It would also mean that the current Polish eastern border would not be a ethinc border as the Curzon line wasn't one - Brest, Lvov, Grondo, Wilno were ethnically Polish and connected to "heartland" Poland with consistent ethnic "belts".