When, Zhu Biao, the first born son of the founder of the Ming dynasty, Zhu Yuanzhang, died on May 17, 1392, Zhu Yuanzhang as his successor chose Zhu Biao's then 15 year old (second) son, Zhu Yunwen, born December 5, 1377.
Zhu Yunwen ascended the dragon throne 21 years old on June 30, 1398 upon the death of his grandfather. But he was only to rule for a mere four years as the 2nd Ming emperor with reign title of Jianwen ("Establishing Civil Virtue").
The Ming empire was at the time divided into areas, each commanded by a Ming prince. Jianwen contrived with his trusted ministers Qi Tai and Huang Zicheng to weaken or eliminate the other princes so as to fortify his own rule.
Throughout 1398 they managed to kill or imprison the Princes of Qi, Dai, Zhou and Xiang. But when it was time to take on his uncle, Prince of Yan and commander of the tough northern frontier army, they soon learned that he was in no mood to let himself be brushed aside.
When envoys were sent north to arrest him, he rose up in rebellion starting a bitter civil war that was to last almost four years.
The empire had a numerically far superior army and the Prince of Yan went into each battle knowing that this could well be his last. But the prince's army mainly consisted of cavalry so he was less dependent on supply lines and by bypassing strongholds, which his cavalry was ill equipped to attack and conquer, he eventually arrived with his armies at the gates of the capital, Nanjing.
The capital fell on July 13, 1402 when key imperial officials betrayed the empire and opened Nanjing's Qinchuan city gate letting in Prince Yan's troops.
The Jianwen emperor had taken shelter inside his imperial capital in Nanjing. In the heat of the battle for the city, fires destroyed the imperial palace and the emperor allegedly perished with his concubines in the flames.
Rumors however soon surfaced with far more popular and romantic versions, for instance that the Jianwen Emperor had managed to escape and lived out the rest of his life as a monk in a monastery.
Zhu Yunwen's uncle, the later Yongle Emperor, spared no effort to erase his nephew from history. He even voided the Jianwen Emperor reign period from history annals, decreed an extension to his father's reign as the Hongwu Emperor from his death in 1398 and until 1402, when the Yongle Emperor usurped the throne.
The Jianwen Emperor's reign title was only restored in 1595. This in turn over the next century spurred innumerous legends hailing the Jianwen Emperor as a benevolent and righteous ruler, who had been brutally removed by a traitor, the Yongle Emperor.
Eventually, in 1736 the Qing dynasty Qianlong Emperor by imperial decision formally restored the Jianwen Emperor's legitimate status as the second Ming emperor.
Since the Jianwen Emperor's fate is unknown then so is the whereabouts of his tomb.
On July 20, a charred corpse was produced and claimed to be that of the Jianwen Emperor. But these were the days before dental record keeping, DNA testing and formal autopsy, so the claim could not be substantiated.
Rumors are nevertheless as mentioned rampant on what happened to the Jianwen emperor.
For instance, Arthur Cotterell in his 2007 book "Imperial Capitals of China" asserts that Zhu Yunwen disguised as a monk escaped to the countryside moving from place to place. Captured in 1441, he was allowed to remain under cover till his death since his usurping uncle had already passed away.
In another version, Zhu Yunwen actually had a chat with members of a search party, sent to look for him by the Yongle Emperor.
The Yongle Emperor even justified the later costly sea journeys by eunuch Zheng He to the Indian Ocean and Africa by claiming that one of the objectives was to search for the Jianwen Emperor.
The official version that he died in the fire could still be true despite the persistent rumors. On the other hand, if the Prince of Yan had indeed been shown the actual body of the Jianwen Emperor the Prince might well have decided to dispose of the remains in an unmarked grave to avoid unwarranted martyrdom by the deceased emperor's followers and family.