Ii Naosuke (1815-1860) was a Japanese warlord and statesman best remembered for opening up Japan to the West by approving the Harris Treaty of 1858, which granted treaty ports and extraterritoriality to the United States of America. Naosuke was also the last defender of the traditional authority of the Tokugawa shogunate.
At the time of his birth in 1815, none would have guessed that Naosuke would one day rise to become the most powerful man in all Japan. Naosuke's family, the Ii, was a prestigious samurai house which had served the Tokugawa dating all the way back to the days of Ieyasu. The fearsome fighters of the Ii, known as the "Red Devils" for their blood-red armor, had been one of Ieyasu's most trusted units, and had fought in the place of honor at the head of his army. Following the great Battle of Sekigahara, the Ii had been awarded part of Ishida Mitsunari's old lands, the prized fief of Hikone on the eastern shore of Lake Biwa. But in later years the Ii receded from the political fore, and by the mid 19th century, no Ii lord had held an important post in the shogunal administration in almost 200 years. Moreover, Naosuke, as the fourteenth son of Ii Naonaka, was not exactly likely to accede as the daimyo at any time in his life. So unlikely in fact, that Naosuke left Hikone to train as a Buddhist monk, living a peaceful life at a mountain lodge in Umoreginoya and subsisting off his meager allotment of 300 koku per annum.
But fate had another plan in store for Naosuke other than a life of quiet asceticism. Over the years all 13 of Naosuke's elder brothers died off or were adopted into other families, such that by the age of 36, he found himself the 12th lord of Hikone domain. Energetic, resourceful, and politically adept, Naosuke entered Edo politics and quickly rose through the ranks of the shogunate. By both family ties and inclination, Naosuke was a conservative, and his rise was undoubtedly abetted by his staunch advocacy of the traditional power arrangements.
Events soon conspired to propel Naosuke to the pinnacle of Japanese politics. In 1853, Perry's Black Ships arrived in Edo Bay, presenting a dire threat to a power arrangement that was dependent on complete and total stasis. In the years that followed, the radical "sonno joi" seclusionist movement swept Japan like wildfire, further undermining an already weakening shogunate with its appeals to imperial authority and its subversive activities against the attempts of the shogunate to deal with the Westerners in good faith.
To make matters worse, the sitting shogun, Tokugawa Iesada, was sickly and apt to die at any moment, despite his relative youth. A battle arose over who should be named Iesada's heir. On one side, the sonno joi partisans sided with disgruntled tozama daimyo to support the candidacy of Hitotsubashi Keiki, a vigorous lord whom the seclusionists hoped would resist western encroachment and the disgruntled daimyo hoped would reform and democratize the government (and incidentally grant them a greater share of power). On the other side was the shogunal bureaucracy, which hoped to maintain the status quo by selecting a weak and controllable heir.
Into this power vacuum stepped Naosuke, whose reliable dedication to the status quo secured his election in 1858 to the position of tairô (大老), or "grand councilor," which was technically the second highest post in the government, but given the state of Iesada's health, in actuality made Naosuke the most powerful man in Japan.
Naosuke quickly took the reins of power firmly in his own hands, using personal connections in the Imperial court to destroy Keiki's chances of being named heir and soon after ordering the approval of the much reviled Harris Treaty (which was really the only option, given the clear military superiority of the United States). Naosuke then proceeded to initiate the "Ansei Purge," imprisoning, executing, or forcing into retirement all supporters of the reformist and seclusionist movements within the government. Whereas in recent years, the shogunate had taken to soliciting the approval of the daimyo before making major decisions, Naosuke reasserted shogunal authority, decreeing that the shogunate was not, nor had ever been, a consultative body, and would no longer require daimyo approval before acting.
For the next two years, Naosuke was master of Japan, and continued to pave the way for further opening of the country to Western powers, while attempting to shore up the shogunate from within, without having to resort to major reform. But the sonno joi movement was far from dead, and the reformist daimyo were content to lie in wait for the time being. On March 3, 1860 a band of samurai assassins, mostly from the sonno joi hotbed Mito domain, ambushed Naosuke's cortege in broad daylight on the street outside the Sakurada Gate of Edo Castle, fighting their way to his palanquin, shooting him at point blank, and making off with his severed head. Naosuke was 46 years old.
Shogunal agents eventually recovered the head, but the last gasp of the Tokugawa bakufu had been breathed. Naosuke had revived the shogunate for a time, but now its decline resumed at greater speed than ever. Just seven years later, the Shogunate would collapse entirely and give way to the Meiji Restoration.