The Jade Emperor in Chinese mythology is one of the representations of the first god. In Taoist theology he is Yuanshi Tianzun, one of the Three Pure Ones, the three primordial emanations of the Tao. He is also the Cao Đài ("Highest Power") of Caodaism. The Jade Emperor is known by many names, including Heavenly Grandfather, which originally meant "Heavenly Duke", which is used by commoners; the Jade Lord the Highest Emperor, and Great Emperor of Jade.
It was said that the Jade Emperor was originally the crown prince of the kingdom of Pure Felicity and Majestic Heavenly Lights and Ornaments. At birth, he emitted a wondrous light that filled the entire kingdom. When he was young, he was kind, intelligent and wise. He devoted his entire childhood to helping the needy (the poor and suffering, the deserted and single, the hungry and disabled). Furthermore, he showed respect and benevolence to both men and creatures. After his father died, he ascended the throne. He made sure that everyone in his kingdom found peace and contentment. After that, he told his ministers that he wished to cultivate Tao on the Bright and Fragrant Cliff.
After 1,750 kalpas, each kalpa lasting for 129,600 years, he attained Golden Immortality. After another one hundred million years of cultivation, he finally became the Jade Emperor (using the given figures, this period before his becoming the Jade Emperor lasted for a total of about 226,800,000 years.)
In the beginning of time, the earth was a very difficult place to live, much harsher than it is now. People had to deal with a variety of monstrous beings, and they didn’t have many gods to protect them; in addition, many powerful demons were defying the immortals of heaven. The Jade Emperor was an ordinary immortal who roamed the earth helping as many people as he could. He was saddened because his powers could only ease the suffering of humans. He retreated to a mountain cave to cultivate his Tao. He passed 3,200 trials, each trial lasting about 3 million years.
On earth at this time, a powerful, evil entity had the ambition to conquer the immortals and gods in heaven and proclaim sovereignty over the entire universe. This evil entity also went into retreat and meditation to expand its power, though later than the Jade Emperor did. He passed through 3,000 trials, each trial lasting about 3 million years. After its final trial, it felt confident that no one could defeat it. It re-entered the world and recruited an army of demons with the purpose of attacking heaven.
The immortals, being aware of the threat, gathered themselves and prepared for war. The gods were unable to stop the powerful demon and it defeated them all.
The Jade Emperor finished his cultivation during this war. When he was changing the land to make it more livable for men and repelling a variety of monsters, he saw an evil glow emitting from heaven and knew something was amiss. He ascended and saw that the evil entity was too powerful to be stopped by the gods. He challenged it, and they fought. Mountains shook and rivers and seas toppled. Due to his deeper and wiser cultivation, his benevolence instead of his might, the Jade Emperor won the battle. After defeating the evil entity, its army was scattered by the gods and immortals. Because of his noble and benevolent deeds, the gods, immortals and humans proclaimed the Jade Emperor the supreme sovereign of all.