Tenshō

Overview

Tenshō (天正) was a Japanese era name (年号, nengō; "year" name) that followed Genki and preceded Bunroku. The era spanned from July 1573 through December 1592, during the Sengoku era, a period of near-constant civil war and political upheaval. It falls within the Azuchi–Momoyama period (1573–1603), a time defined by the rise of powerful warlords who sought to unify Japan under a single authority.

The reigning emperors during Tenshō were Ōgimachi-tennō (正親町天皇) and Go-Yōzei-tennō (後陽成天皇). Ōgimachi abdicated in 1586, and Go-Yōzei took the throne in the same year, well before the era name itself came to an end.

What Defined the Era

Tenshō was the era of national unification. When it began in 1573, the warlord Oda Nobunaga had already driven the last Ashikaga shōgun from Kyoto, effectively ending the Ashikaga shogunate. The era name was chosen to mark a new beginning, and it carried the weight of that political rupture.

The era is closely tied to the careers of two men: Oda Nobunaga and his successor, Toyotomi Hideyoshi. Nobunaga spent the early years of Tenshō consolidating his control over central Japan, dismantling rival warlords and Buddhist monasteries that had resisted his authority. His death in 1582, at the hands of his general Akechi Mitsuhide, threw the country into a brief but violent succession struggle. Hideyoshi emerged victorious from that struggle and spent the remainder of the era extending unification across the entire archipelago.

The era also saw the first sustained contact between Japan and European powers. Portuguese and Spanish traders and missionaries had arrived decades earlier, but during Tenshō their influence peaked. Jesuit missionaries, led by figures such as Alessandro Valignano, secured permission to preach and built churches in Kyoto and elsewhere. A delegation of young Japanese Christian envoys, known as the Tenshō embassy, travelled to Europe in 1582 and returned in 1590, bringing back a printing press and Western knowledge.

Key Events

The Tenshō era opened with a decisive act: in 1573, Oda Nobunaga expelled the shōgun Ashikaga Yoshiaki from Kyoto, formally ending the Ashikaga shogunate. That same year, Nobunaga destroyed the Asakura and Azai clans at the Battle of Anegawa, removing two of his most dangerous rivals in the north.

In 1575, Nobunaga won the Battle of Nagashino against the Takeda clan, a victory famous for his innovative use of massed arquebus fire behind wooden palisades. The battle broke Takeda military power and opened the way for Nobunaga's advance into eastern Japan.

In 1582, Nobunaga was betrayed and killed at Honnō-ji temple in Kyoto by Akechi Mitsuhide. Hideyoshi, then campaigning in the west, rushed back, defeated Mitsuhide at the Battle of Yamazaki, and avenged his lord within days. Hideyoshi then moved to consolidate power, and by 1585 he had been appointed kampaku (関白; regent) by the imperial court, a title that gave him formal authority over the entire realm.

In 1586, the Tenshō earthquake struck central Japan. It was one of the most destructive earthquakes in Japanese history, killing thousands and causing widespread damage in the Kansai region. The same year, Emperor Ōgimachi abdicated, and Go-Yōzei ascended the throne.

In 1587, Hideyoshi issued the first of his "sword hunts" (刀狩, katana-gari), ordering the confiscation of weapons from farmers and monks. The policy was designed to separate the peasantry from the warrior class and to prevent future uprisings. In the same year, he expelled the Jesuit missionaries from Japan, a reversal of the tolerance they had enjoyed under Nobunaga.

In 1590, Hideyoshi completed the conquest of the Hōjō clan at the Siege of Odawara, bringing the last major independent domain under his control. The following year, he began preparations for an invasion of Korea, a campaign that would launch in 1592, the final year of the Tenshō era.

The Name in Japanese

The era name is written 天正 in kanji. Its kana reading is てんしょう, and its romaji form is Tenshō.

The name is composed of two characters:

• 天 (てん, ten): "heaven" or "celestial." This character appears in words like 天気 (てんき, tenki; "weather") and 天国 (てんごく, tengoku; "heaven"). It carries a sense of the divine or the cosmic order.

• 正 (しょう, shō): "correct," "righteous," or "proper." This character appears in words like 正しい (ただしい, tadashii; "correct") and 正月 (しょうがつ, shōgatsu; "New Year"). It implies legitimacy, order, and moral rightness.

Together, 天正 can be read as "heavenly correctness" or "righteous heaven." The name was chosen to signal a restoration of proper order after the chaos of the preceding era, and it was likely inspired by the Chinese phrase tianzheng, which appears in classical texts. The era name was also referenced by the Battle of Tianzheng, a conflict in China that shares the same characters, though the Japanese era name was chosen independently.

How the Era Name Works

Japanese era names, or nengō (年号), are a system of dating that counts years from the start of a named period rather than from a fixed epoch. The system was adopted from China in the seventh century and has been used in Japan ever since, with only brief interruptions.

An era name is proclaimed by the imperial court, usually at the beginning of a new emperor's reign or to mark a significant event. The name is chosen for its auspicious meaning, and it is expected to reflect the hopes of the court for the years ahead. Tenshō was proclaimed in 1573, in the midst of the Sengoku era, and its meaning of "heavenly correctness" was a deliberate statement of intent.

During the Tenshō era, the system worked as follows: the first year of the era, Tenshō 1, began in 1573 and ran until the following New Year. Each subsequent year was numbered sequentially, so Tenshō 2 corresponded to 1574, Tenshō 3 to 1575, and so on. The era ended in December 1592, when a new era name, Bunroku, was proclaimed to mark the beginning of Hideyoshi's invasion of Korea.

The nengō system was not merely a bureaucratic convenience. It was a tool of political legitimacy. Whoever controlled the imperial court controlled the era name, and warlords like Nobunaga and Hideyoshi used the court's authority to sanction their rule. When Hideyoshi was appointed kampaku in 1585, the era name Tenshō lent his regime an air of divine sanction, and when he needed a fresh start for his Korean campaign, he simply changed the era name to Bunroku. The era name was, in effect, a statement of who held power and what that power claimed to stand for.