Another book from the 1632 series and a direct sequel to 1634: The Galileo Affair. Fortunately, this one is much better than Grantville Gazette III.
The Americans from the future have established an embassy in Rome, as well as a tavern catering to the revolutionary-minded elements. Cardinal Borja, head of the Spanish Inquisition, is enraged by the accommodation reached by Pope Urban, and he foments unrest leading to an attempt to overthrow the pope.
Fairly entertaining with a coherent plot and engaging characters. The first half moves slowly as the background is laid down; the pace picks up as unrest escalates into war.