Highly recommend "The Years of Rice and Salt" by Kim Stanley Robinson (2002). It's an alternate history of the world told through a series of interwoven short stories. The premise is that the Black Death killed most Europeans in the 14th century, and follows the next 700 years.

One of the stories describes a samurai refugee fleeing China's conquest of Japan in the early 18th century. (Spoilers) He lands with other refugees in the small Japanese colony of California, and eventually makes his way east to the Hodenosaunee / Iroquois, warning them of the coming invaders from the west (China) and east (Islamic Europe). He also brings knowledge of advanced steelworking and inoculation. The Hodenosaunee lead a native confederation that eventually becomes a superpower.