They were Polish territories because Poland held and administered them. They were also part of the PLC before the Russian empire seized them…
https://en.wikipedia.org/wiki/Partitions_of_Poland
We can argue all day about what conditions grant a right to a territory. Or we can cut the bullshit and stop pretending that the Soviets sending the Red Army across the Polish border to conquer land, while raping the inhabitants, was anything but an invasion.

















IIRC we don’t know when life started on earth because records of the early earth aren’t available - geological activity recycled the surface. What evidence we do have is that life started pretty much as early as the records we have can show, meaning either it appeared very quickly once the planet cooled or was already present.