Solidarity 25 years

Yesterday was the 25th anniversary of the birth of Solidarity, Poland’s first free union movement, one of the most notable first steps to democracy in Eastern Europe:

I was just old enough to have some understanding of world events and politics back then. I remember thinking it was neat, and wondering whether it would actually matter in the long run.

Does anyone have a recommendation for a good book about this period, and the general failure of the communist system in its wake? Ideally not something focused on a particular political agenda.