A long debate has existed over whether or not the Yan Emperor was the same person as the legendary Shennong. An academic conference held in China in 2004 achieved general consensus that the Yan Emperor and Shennong were the same person. Another possibility is that the term Flame Emperor was a title, held by dynastic succession, with Shennong being known as Yandi, perhaps posthumously. Accordingly, the term Flame Emperors would be generally more correct. The succession of Flame Emperors, from Shennong, the first Yandi, to the last, defeated by Huangdi, may have lasted some 500 years.