Tenpō (天保) was a Japanese era name (年号 nengō, "year name") after Bunsei and before Kōka. The period spanned from December 1830 through December 1844. The reigning emperor was Ninko-tennō (仁孝天皇).
The Tenpō era is often described as the beginning of the end of bakufu government. Though the era accomplished much through its reforms, and also culturally speaking, the injury inflicted on the Tokugawa system of government during the Tenpō period was unparalleled. Public order and dissatisfaction with government was a main issue, but the bakufu was not entirely at fault for the stir amongst the people. For example, the failure of crops in 1833, which soon became a lengthy disaster endured for over four years called the Great Tenpō famine, was caused mainly due to poor weather conditions. Because crops could not grow under these circumstances, prices began to skyrocket. These dire circumstances sparked many rebellions and riots across Japan over the course of the Tenpō years. Weary and desperate for someone to blame, the people rose up against the government, and Ōshio Heihachirō, known for leading one of the largest rebellions, made a statement to implicate "the natural disasters as sure signs of Heavens's discontent with the government".Mizuno Tadakuni's reforms were meant to remedy these economic issues, but the reforms could not rescue the bakufu from its ultimate collapse.
The shogunate rule during the Tenpō era was that of Tokugawa Ieyoshi, the 12th shōgun' of the bakufu government. His reign lasted from 1837 to 1853. During this time, many factors appeared to have seen to the decline of his health: namely, the great and devastating famine, the many rebellions rising up against the bakufu, and the swift advance of foreign influence.
The Great Tenpō famine of the 1830s was a devastating term in which the whole of Japan suffered rapidly decreasing temperatures and loss of crops, and in turn, merchant prices began to spike. Many starved to death during this grim time: "The death rate for a village in the northeast rose to thirty-seven per thousand and that for the city of Takayama was nearly forty-five". As crops continued to decline in the countryside, prices increased, and a shortage of supplies left people competing to survive on meager funds. The rising expense of rice in particular, a staple food of the Japanese, was a firm blow to both the economy and the people, who starved because of it. Some even resorted to "eating leaves and weeds, or even straw raincoats".