As you approach the Palace of Heavenly Purity (Qianqing gong), the first grand hall in the Inner Court of the Forbidden City, look up, and you’ll see a large plaque hanging prominently in the centre. It bears four majestic characters: “Let the Righteous Shine” (Zheng da guang ming). This phrase signifies that the emperor’s rule over the nation must be fair and aboveboard.
This plaque is one of the most legendary symbols in the Forbidden City, and with the embellishment of recent films and TV dramas, it has become almost emblematic of the Qing dynasty (1644–1911)—because it “decided” who would ultimately inherit the throne.
In ancient Chinese society, the throne was typically inherited by the firstborn son of the empress—a system known as the “primogeniture”. This meant that priority went to the eldest son of the empress. Another method was “appointing the worthy”, which evaluated each prince’s virtues and behaviour. The least favoured was “appointing the beloved,” namely that the emperor simply chose his favourite son as heir. Although this method existed in history, it was rare, as it often led to fierce power struggles in the palace.
In the Qing dynasty, Hong Taiji (r. 1636–1643), son of Nurhaci (r. 1616–1626), founder of the Qing dynasty, was chosen as ruler through the selection of eight Beile (Prince of the Third Rank). Similarly, Hong Taiji’s son, Fulin, ascended the throne similarly. Emperor Kangxi (r. 1661–1722) took the throne at six, a decision made by his grandmother, Empress Xiaozhuangwen (1613–1688), and approved by Emperor Shunzhi (r. 1643–1661). However, their successions were besieged by intense and complex power struggles, greatly impacting the stability of the Qing rule.
Early on, Emperor Kangxi recognized that the lack of rules in throne succession created many problems for governance, so he attempted to establish the system of primogeniture and appointed his eldest legitimate son as the heir. However, he soon found that growing up in a position of unmatched privilege made the crown prince increasingly arrogant and temperamental. Meanwhile, other princes secretly harboured resentment, leading to further instability in court affairs.
As depicted in many palace dramas, after Emperor Kangxi’s death, his fourth son, Yinzhen, emerged unexpectedly, seizing the throne and becoming Emperor Yongzheng (r. 1722–1735). Having experienced fierce power struggles himself, Emperor Yongzheng resolved to reform the imperial succession process. He devised a “secret succession” system by writing his chosen heir’s name in a sealed edict kept inside the “heir designation box”. During his lifetime, the emperor would not reveal the identity of his chosen successor; only after his death would the box be opened. This approach brought many advantages: it reinforced the reigning emperor’s absolute supremacy, avoided disputes over succession, and provided equal opportunities, allowing the princes to fully demonstrate their abilities and strive for excellence. So, where was this box kept? Behind the “Let the Righteous Shine” plaque in the Palace of Heavenly Purity, of course.
Thirteen years after the establishment of this system, Emperor Yongzheng passed away. Prince Zhuang, Yunlu (1695–1767), opened the heir designation box and revealed the secret edict, announcing that Prince Bao, Hongli, would inherit the throne, becoming Emperor Qianlong (r. 1735–1796). So, Emperor Qianlong was the first Qing emperor to ascend the throne through the secret succession system.
In the 38th year of his reign (1773), Emperor Qianlong also selected his successor through this secret method. Twenty-two years later, he decided to retire and become Emperor Emeritus. He retrieved the secret edict and, under his personal supervision, declared his fifteenth son, Yongyan (later Emperor Jiaqing), as crown prince and officially passed the throne to him.
In the years that followed, Emperor Jiaqing (r. 1796–1820) and Emperor Daoguang (r. 1820–1850) continued this method of choosing an heir. However, as the Qing dynasty declined in power and the imperial family dwindled in numbers, the practice faded. When Emperor Xianfeng (r. 1850–1861) died, his only son, a six-year-old, succeeded him as Emperor Tongzhi (r. 1861–1875). Upon Tongzhi’s death, without an heir, the practice of secret succession became obsolete.
Because it once held the power to decide the fate of the Qing emperor candidates, the “Let the Righteous Shine” plaque in the Palace of Heavenly Purity commands unparalleled reverence and has captured the imagination of generations since.