Eiwa

Overview

Eiwa (永和) was a Japanese era name (年号, nengō, literally "year name") of the Northern Court during the Era of Northern and Southern Courts. The era followed Ōan and preceded Kōryaku, spanning from February 1375 through March 1379. The emperor in Kyoto during this period was Emperor Go-En'yū (後円融天皇, Go-En'yū-tennō), while the Southern Court rival in Yoshino was Emperor Chōkei (長慶天皇, Chōkei-tennō). Eiwa belongs to the Muromachi period (1336 – 1573).

What Defined the Era

The Eiwa era unfolded against the backdrop of the Nanboku-chō, the decades-long split between two imperial lines. The Northern Court, based in Kyoto, held the capital and the shogunate's backing, while the Southern Court operated from Yoshino, maintaining its claim to legitimacy. Emperor Go-En'yū occupied the throne in Kyoto, but the Southern Court's Emperor Chōkei continued to press his own claim, keeping the dynastic conflict alive.

This was also a period of shifting power within the Ashikaga shogunate. The shogun Ashikaga Yoshimitsu was consolidating authority, and the era's political life was marked by the ongoing friction between the shogunate, the court nobility, and the rival imperial faction. The era name itself was proclaimed in February 1375, a standard practice upon imperial succession or auspicious renewal, though the underlying tensions of the dual-court system never fully receded.

Key Events

The Eiwa era is not associated with a single dramatic turning point in the historical record. Instead, it was a stretch of continued military and political maneuvering between the Northern and Southern Courts. The Southern Court's forces remained active in various provinces, and skirmishes persisted along the contested frontiers. The shogunate under Yoshimitsu worked to extend its grip over regional warlords, many of whom hedged their loyalties between the two imperial lines.

In March 1379, the era name was changed to Kōryaku. Such changes were often prompted by calendrical cycles, natural omens, or courtly affairs, and the transition from Eiwa to Kōryaku followed this established pattern. The era thus closed without a singular defining event, but as a segment within the longer struggle that would eventually see the Southern Court's surrender in 1392.

The Name in Japanese

The era name is written 永和 in kanji.

• Kana reading: えいわ
• Romaji: Eiwa

The name breaks down into two characters:

• 永 (ei): meaning "eternal" or "long-lasting." In this word it carries the sense of permanence and endurance, a common aspiration in era names.
• 和 (wa): meaning "harmony" or "peace." This character appears frequently in Japanese era names and in the word for Japan itself (日本, Nihon, though the "wa" reading here is different). Together, 永和 conveys the idea of "eternal harmony" — a hopeful proclamation for the realm.

The reading えいわ is a straightforward on'yomi (Sino-Japanese reading) of both characters: 永 as えい and 和 as わ. This is typical for era names, which were almost always drawn from classical Chinese texts and read in their Chinese-derived pronunciation. The choice of such auspicious characters reflects the court's intent to invoke stability and peace, even as the era itself unfolded amid civil strife.

How the Era Name Works

A Japanese era name, or nengō (年号), is a system of dating that counts years from the proclamation of a new era. The practice originated in China and was adopted in Japan in 645 with the Taika era. Each era name is composed of two kanji, selected for their auspicious meanings, and the era begins on the day it is proclaimed, not on a fixed calendar date.

During the Nanboku-chō period, the system operated in parallel: both the Northern and Southern Courts issued their own era names, each recognizing its own emperor. This is why Eiwa is specifically identified as a Northern Court era. The Southern Court used its own sequence of names, and the two systems ran concurrently until the courts were reunited.

The era name changes for reasons such as imperial accession, natural disasters, or auspicious signs. When a new era is proclaimed, the previous era ends immediately, and the new one begins. This means that a single Gregorian year can contain portions of two different Japanese eras. The Eiwa era, for instance, began in February 1375 and ended in March 1379, with the change to Kōryaku taking effect mid-year.

In modern Japan, the nengō system continues with the reign of each emperor, but during the Muromachi period it was a fluid and politically charged tool. Control over era names was a symbol of legitimacy, and both courts used their proclamations to assert their authority. The Eiwa era, as a Northern Court designation, was part of that ongoing contest for the right to define time itself.