Japan officially adopted the Gregorian calendar in 1873. Before this, the country used the Imperial Year System and the Japanese Era Name System (Gengō) to track time. While the Imperial Year System is no longer in use, the Era Name System remains an important part of Japanese culture and is still used alongside the Western calendar, particularly for government documents, historical records, and commemorative events.
How the Era Name System Works
The Japanese Era Name System is based on the reign of the emperor. Each emperor’s reign is assigned a unique era name, and the era ends when the emperor either abdicates or passes away. The current era is the Reiwa Era (令和), which began on May 1, 2019, following the abdication of Emperor Akihito. His son, Emperor Naruhito, ascended the throne on this day, marking the official start of the Reiwa Era.
When an emperor passes away, they are posthumously referred to by their era name. For example:
Emperor Hirohito, who reigned from 1926 to 1989, is now known as Emperor Showa.
Emperor Akihito, who reigned from 1989 to 2019, will be known as Emperor Heisei after his death.
The late Emperor Mutsuhito, who reigned from 1868 to 1912, is remembered as Emperor Meiji.
This naming tradition helps define historical periods in Japan, and many people still use era names when referring to significant events in Japan’s history.
Origins of the Modern Era System
The Japanese era system in its current form has remained unchanged since the Meiji Restoration in 1868. Prior to this, an emperor’s reign could span multiple era names, as new eras were sometimes declared in response to significant events such as disasters or political shifts.
The Meiji Era (1868–1912) marked the beginning of modern Japan. It followed the fall of the Edo period (1603–1868), during which Japan was ruled by the Tokugawa shogunate, a military government that controlled the country for over 250 years.
The Edo Period and Japan’s Isolation
The Edo period began in 1603 when the Tokugawa shoguns came to power and established their capital in Edo (modern-day Tokyo). Under Tokugawa rule, Japan adopted a policy of national isolation (Sakoku), heavily restricting foreign trade, travel, and even the importation of foreign books.
However, this isolation came to an abrupt end in 1853, when Commodore Matthew Perry of the United States Navy arrived in Edo Bay with a fleet of warships. Perry demanded that Japan open its ports to foreign trade, ultimately leading to the collapse of the shogunate’s power.
The Boshin War and the Meiji Restoration
By the 1860s, dissatisfaction with the Tokugawa Shogunate was growing, and a movement to restore imperial rule gained momentum. This led to the Boshin War (1868–1869), a civil war between forces loyal to the emperor and those supporting the shogunate.
In 1868, Emperor Meiji was restored to power, marking the beginning of the Meiji Era. He moved into Edo Castle, and the city was renamed Tokyo, meaning “Eastern Capital.” Under his rule, Japan rapidly modernised, adopted a constitutional monarchy, and established a parliamentary system known as the Imperial Diet.
The Succession of Emperors in Modern Japan
Since the Meiji Restoration, Japan has had the following emperors:
Emperor Meiji (1868–1912) – Oversaw Japan’s transformation into a modern state.
Emperor Taisho (1912–1926) – Remembered for a period of political liberalism known as “Taisho Democracy.”
Emperor Showa (1926–1989) (Hirohito) – Reigned during WWII and Japan’s post-war recovery.
Emperor Heisei (1989–2019) (Akihito) – Led Japan through an era of economic challenges and stability.
Emperor Reiwa (2019–Present) (Naruhito) – The current emperor, leading Japan into the modern era.
The Role of Eras Today
The Japanese era name system remains an important cultural and historical marker, helping define different periods in the country’s history. While the Gregorian calendar is Japan’s official calendar today, the era system continues to be widely used in official documents, historical references, and even daily life. Understanding this system offers insight into Japan’s unique historical continuity and respect for tradition.
