Grantville occupies the same spot on the map of West Virginia as the real-world town of Mannington. It is modeled on Mannington as it existed in the spring of 2000, though it is not an exact copy. The small community of Rachel, located 2 miles (3.2 km) east-southeast of Mannington, is possibly the basis for Grantville's satellite community of Deborah.
In the spring of the year 2000, Grantville was transported to Germany in the midst of the Thirty Years' War by the Assiti Shards effect (known by the locals of Grantville as the "Ring of Fire"). Shortly following the event and the townspeople's discovery of their situation, the selected leaders of Grantville, led by Mike Stearns, decided to adjust the town's involvement to their new world by declaring Grantville as part of the sovereign "New United States" (NUS).
Throughout 1631 and into 1632, Grantville allied with neighboring free towns and cities such as Jena and Badenburg to "expand" the New United States, and became involved in several battles to defend allied territory which were pivotal in the rapid growth of the new (and radical to 17th-century thought) "United States".
The town loosely allied with Swedish King Gustavus Adolphus against the Catholic League led by the Kingdom of Spain and Holy Roman Empire over the winter of 1631–32. The following summer, the Americans had organized a mixed army of down-timer Germans and up-timer Americans to protect the region. While arrangements with Gustav were cordial, the two sides were not close until the up-timers used their influence to arrange favorable financial terms for Gustav to borrow funds for his war aims. Among other things, the New United States had expropriated the Thuringian territories of Gustav's only reliable German allies, the Duke of Saxe-Weimar and his brothers.
France's Cardinal Richelieu learned Grantville and fearing its potential effect on Europe and its status quo, he commanded Albrecht von Wallenstein to direct an attack with the goal of destroying the town. Wallenstein engaged 2,000 Croatian cavalrymen to "Kill all the Jews" in Grantville. Through his spies, Wallenstein had determined the heart of Grantville was its knowledge base— and gave orders to destroy Grantville's high school and its library. The raid came as a surprise to the people. Although most of Grantville's soldiers were absent, the townspeople held off the raiders until a timely rescue from Gustavus Adolphus (under the alias "Captain Gars") and his small force of 400 Laplanders and Finnish light cavalry. The raid forced Michael Stearns to recognize the inevitable and ally the NUS with Gustavus.
Under the new United States of Europe, Grantville became the provincial capital of the State of Thuringia-Franconia and the Grantvillers found themselves administering the conquered territory of Franconia as well as their parts of Thuringia—most of which belonged to the Dukes of Saxe-Weimar, including nearby free cities and towns.
- Grantville High School
- Higgins Hotel
- Leahy Clinic
- Manning Assisted Living Center
- Thuringen Gardens
- Club 250
- Grantville Fine Foods