1632 by Eric Flint - It's an alternative history in which the real town of Mannington, Virginia is fictionalized as "Grantville" and thrown back in time to 1631 Germany, causing it's citizens to band together, and kick off the American Revolution more than a Century Early.
It's a fascinating study of society and the infrastructure that makes civilization work. Their struggles to avoid starvation and being over-run by the armies of the 30 years war are gripping reading.
It was so popular it spawned a community of writers and a series that lived until the authors demise a few years ago.