On March 8, 1421, the largest fleet the world had ever seen set sail from China "to the ends of the earth". When it returned in October 1423, the emperor had fallen, leaving China in political and economic chaos. The great ships were left to rot at their moorings and the records of their journeys were destroyed. Lost in China's long, self-imposed isolation that followed was the knowledge that the Chinese had reached America seventy years before Columbus and had circumnavigated the globe a century before Magellan. They had colonized America before the Europeans and had transplanted in America and other countries the principal economic crops that have fed and clothed the world.

Unveiling incontrovertible evidence of these astonishing voyages, 1421 rewrites our understanding of history in a landmark work of historical investigation.