Grantville, West Virginia, in the year 2000, is transposed within an area of southern Thuringia of Germany in the 1630s. Grantvillers subsequently take on the Holy Roman Empire's troops in the Thirty Years' War, to maintain their own town's integrity.^[2]

Grantville joins sides with Gustavus Adolphus, and tries to recreate the Germanies in the image of the United States.^[4]

A diplomatic and trade mission to the Italies goes awry when youngsters attached to the mission decide to rescue Galileo from the Inquisition, and end up in a plot to assassinate the Pope. The plot is hatched by a French operative turned rebel, who wishes to destroy France to allow the rise of the Huguenots.

Cardinal Borja, incensed with the behavior of Pope Urban, decides to assassinate the Pope and his political allies and to have himself declared the new Pope. Though Borja manages to take over the Vatican and establish quorum with cowed Cardinals, the old Pope escapes.

Western Europe maneuvers to contain Gustavus Adolphus, resulting in a naval battle in the Baltic, and the conquest of Denmark by Sweden, and victory for Grantville's navy of ironclads.

The Prince Cardinal Infante of Spain takes on vice-regal duties in the Spanish Netherlands, then decides to separate from Spain and declare himself King. With the aide of Grantvillers, he acquires a bride in the rebellious daughter of the Holy Roman Emperor, Duchess Anna Maria.

A French Huguenot rebel plots to blame Richelieu for an attack on Grantville. Focuses chiefly on the lives of mid-level government employees and private citizens of Grantville following the end of those prior novels, and leading to major political changes throughout the USE.

Sweden and USE invade Poland, Gustavus Adolphus is seriously injured, and the invasion comes to a halt. Episodes five and six of The Anaconda Project, an interrupted series in Grantville Gazette volumes 12–21, were incorporated into chapters four and five of 1635: The Eastern Front.

Oxenstierna usurps the power of USE parliament, sides with the nobility, and forces the country into a civil war which is ultimately won by supporters of FoJP and CoC led by Mike Stearns.

Bernie Zeppi takes a job as technical adviser to the Russians' attempt to bootstrap themselves into an industrial revolution.

The Pope is pursued across Italian countryside by assassins sent by Borja, while the USE mounts commando raids to rescue Frank Stone and his wife from Spanish captivity.

Eddie Cantrell and Anne Cathrine marry and are sent by Admiral Simpson to Caribbean to secure access to the Jennings Oil Field. Naval battle ensues with the Spanish and settlers which ends in a standoff.

The Barbie Consortium travel to Vienna as part of a plan to fix the Austro-Hungarian economy and defend its future. Meanwhile, the Ottomans, flush with victory, turn their gaze to Europe and their old enemy.^[14]

Cardinal Richelieu's position in France is further threatened by Gaston, the younger brother of King Louis XIII, while the same monarch and his wife devise a plan to protect the throne from his ambitious brother and enemies.^[16] This book was a finalist for the 2016 Dragon Award for Best Alternate History Novel.^[17]

Cromwell and the Americans flee north to Scotland to escape King Charles of England and his new Prime Minister the Earl of Cork. This book was a finalist for the 2016 Dragon Award for Best Alternate History Novel.^[17]

The USE's war with Poland enters a new stage while the invasion of Bavaria comes to a conclusion. Meanwhile, the Ottoman Empire comes ever closer to their long-sought goal of capturing Vienna.^[14][19] This book was a finalist for the 2017 Dragon Award for Best Alternate History Novel.^[20]

Urban VIII pulls together a consistory as a mini-Vatican II and is then assassinated. Cardinal Bedmar is elected as the new Pope but Borja still occupies the Vatican. Results in a deep divide within Catholicism; Spain, Poland, Bavaria go for Borja in Rome, deep division within Austria.^[14]

Czar Michael Romanov and his supporters withstand the siege of Ufa, his new capitol. The Czar sends envoys beyond the Urals and establishes a Constitutional Convention for a new Russian Empire.

The Ottomans continue with their invasion of Austria. At the same time, Saxony seized control of Lower Silesia, a region that has been in dispute with Poland for almost a century. Polish revolutionaries seized control of Galicia while Bohemia also became involved in that regional conflict. Includes (parts from) The Anaconda Project, an interrupted series in Grantville Gazette volumes 12–21.