I'm involved in the Poland Regional DNA Project, I designed their map of Poland's "genetic regions" and wrote "Historical Context":
https://www.eupedia.com/genetics/reg...t_poland.shtml
Those regions are only preliminary. Geographical coordinates will be assigned to participants based on birthplaces of ancestors. Just like in the People of the British Isles Project, we welcome everyone with grandparents born within 80 km (50 miles) of each other in areas of present-day Poland:
https://www.peopleofthebritishisles.org/
Information about birthplaces of great-grandparents is also important, please provide it as well if you decide to join the Project.