Though the Thirty Years' War continues to ravage 17th-century Europe, history as it once happened has been strongly deflected by the new force that is rapidly gathering power and influence: the United States of Europe, an alliance between Gustavus Adolphus, King of Sweden, and the West Virginians from the 20th century, led by Mike Stearns, who were hurled centuries into the past by a mysterious cosmic accident - the Ring of Fire.
The USE has know-how of 20th-century technology, but the American traditions of freedom and justice are having an even stronger impact on Europe, and the rulers of Europe are powerless to stuff the Grantville genie back into the bottle.
