Most of Central Europe was conquered by the Turks, who occupied it until the twentieth century, leaving it in no shape for colonization of much of the non-European world as in our timeline. Constantinople was conquered in 1420, the Ottomans moved into Vienna in 1440, and took over Paris in 1460, before invading the British Isles in 1490. The greater virulence of the Black Death in Europe allowed non-European powers to emerge. In Eastern Asia, Russia and Japan are now the main powers. By contrast, Turkey has undergone a period of instability that cost it control over the United Kingdom, from which it was expelled in the early twentieth century due to the leadership of a new royal dynasty inaugurated by "James the Valiant. The narrator and protagonist is eighteen-year-old Dan Beauchamp, who travels from impoverished England in 1967 to seek his fortune in the Aztec Empire.