Historian Naotsugu Hamada has proposed a new theory about the 1613 mission that Date Masamune, Sendai's then-feudal lord, sent to Europe and Mexico, arguing that he may have intended to use funds from trade with Mexico to reconstruct Tohoku, which had been rocked by a quake-tsunami disaster just two years earlier.

It is traditionally believed that Date (1567-1636), who built Sendai Castle and founded the city, dispatched the Keicho mission, named after the contemporary era, purely to boost his own name and reputation.

But the 73-year-old Hamada, a resident of Sendai, came up with the alternative theory after the city and many other areas in the northeast were devastated by the March 11, 2011, killer quake and tsunami.