GATE OF WORLDS (Ibooks Science Fiction Classics)

In this alternate history novel, the Bubonic Plague sets the stage for a world where the West is powerless. After the Black Death has wiped out most of the European population, there is little defense against Turkish invasion and expansion, and by the 1980s, the major world powers are the Russians, the Turks, the Aztecs, the Incas, and the Japanese. Dan Beauchamp, a young Englishman whose heart longs for fortune and adventure, travels to industrial Mexico and discovers that he has a lot to learn.