What's done is done. But what if a historic negotiation over the surrender of Edo Castle between Saigo Takamori, who led the Imperial forces during the fall of Edo, and Katsu Kaishu, the shogunate's army minister, had fallen through 150 years ago? The surrender of the fort, or the collapse of the Tokugawa shogunate, which opened the door to Japan's modernization, might not have happened, and what is now the nation's capital could have gone up in flames. Edo, renamed Tokyo in September 1868, was controlled by the shogunate for 260 years, but it fell to the alliance of Satsuma and Choshu forces supportive of the formation of a new government under the restored Imperial rule of Emperor Meiji. One of the central conditions for the peaceful handover, which saved Edo and its population of more than 1 million from war, was to spare the life of Tokugawa Yoshinobu, the 15th and last shogun. Emperor Meiji moved from Kyoto to his new residence in the castle, which today is part of the Imperial Palace in Tokyo.