Emperor Taizong died in 649 and was succeeded by his son and crown prince
Li Zhi (as Emperor Gaozong). He became an assistant chancellors and over time gained higher status. By 664, Empress Wu's influence on the governance of the country had angered Emperor Gaozong so much that he had Chancellor
Shangguan Yi draft an edict for her deposition. Empress Wu pleaded with Emperor Gaozong, who relented and In this purge, Hao Chujun was also somewhat reduced. Shangguan was subsequently executed and, from then on, Empress Wu would sit behind a curtain beside Emperor Gaozong and give him advice during imperial meetings and most of the key decisions until the end of his reign were made by Empress Wu. Around the new year 667, Emperor Gaozong commissioned the chancellor
Li Ji to command a major attack on
Goguryeo, and Hao Chujun was made an assistant to Li Ji, a campaign during which Hao served with distinction. In one particular incident, Hao, who was said to be obese, was approaching a Goguryeo city when Goguryeo forces launched a surprise counterattack, causing much alarm for Hao's soldiers. Hao, who was said to be obese, did not panic, and instead pulled out a chair and sat down to eat his rations, while secretly ordering his elite troops to attack Goguryeo forces, defeating them. His calmness impressed his troops. As of 668, Hao was
Dong Tai Shilang (東臺侍郎) — deputy head of the examination bureau of government (東臺,
Dong Tai) — when Emperor Gaozong became convinced that a
Hindu monk, Lujia Yiduo (盧迦逸多), was capable of creating medicine that would bestow immortality. He therefore commissioned Lujia as a general and was poised to take the medicine that Lujia created. Hao spoke against it, pointing out that immortality is impossible and that taking such medicine could have caused Emperor Taizong's death previously. Emperor Gaozong took his advice and did not do so. In 669, he gave Hao the designation
Tong Dong Xi Tai Sanpin (同東西臺三品), making Hao a chancellor
de facto. Around new year 671, when Emperor Gaozong changed the officials' titles to the ones that were used before 662, Hao's title was changed to
Huangmen Shilang (黃門侍郎). At times, when Emperor Gaozong was at the eastern capital
Luoyang, he would put the crown prince
Li Hong in charge of the capital
Chang'an, and generally, all of the chancellors remained at Chang'an to assist Li Hong, except that Hao attended to Emperor Gaozong. In 672, Hao was given the honorific title
Yinqing Guanglu Daifu (銀青光祿大夫) and made
Zhongshu Shilang (中書侍郎), the deputy head of the legislative bureau of government. In 673, he was put in charge of revising the imperial records, as it was suspected that the previous lead editor,
Xu Jingzong, had made many inaccurate records. In 674, during an imperial feast, for entertainment, Emperor Gaozong divided the imperial musicians into two teams and ordered that his sons
Li Xián the Prince of Yong and
Li Xiǎn the Prince of Zhou (note tone difference) lead the two teams in a competition. Hao, immediately argued against it: Both Emperor Gaozong and Empress Wu was surprised by but agreed with Hao, and both cancelled the competition. Over the many years, especially in 675, Emperor Gaozong, suffering from a dizzying illness (may be
hypertension) that caused serious headaches, considered making his powerful and domineering wife
Empress Wu regent and she would formally rule the empire. He consulted the chancellors, and Hao spoke against it: Another official,
Li Yiyan, also spoke against the idea, and Emperor Gaozong did not carry it out and still Empress Wu continued to "Ruling behind the curtain". because of this current of opposition Hao, From this point on, Empress Wu was said to be resentful of Hao, but as Hao always acted appropriately and was without fault, she could not find a way to accuse him of crimes, instead in 675, she decided to divide the chancellors power within the government to prevent future opposition to her power, and by forming her own literary scholars, the "North Gate Scholars", she divided power between the State Secretariat and her secret secretariat. Later in 675, Emperor Gaozong made Hao
Zhongshu Ling (中書令), the head of the legislative bureau and a post considered one for a chancellor. In 677, he gave Hao an additional title as staff member for Li Xián, who had become crown prince after Li Hong's death in 675, as well as the honorific
Jinzi Guanglu Daifu (金紫光祿大夫). In 679, Hao was made
Shizhong (侍中), the head of the examination bureau and still chancellor. In spring 681, he was made advisor to Li Xiǎn (whose name had been changed by this point to Li Zhe), who was made crown prince in 680 following Li Xián's removal. Hao was by Empress Wu removed from his post as chancellor. He died later that year and was buried with great honor, but at the request that Hao himself had made prior to his death, submitted by his son Hao Beisou (郝北叟), not with great amount of material. == After death ==