Career
Yang June was from Hongnong Commandery (弘農, roughly modern Sanmenxia, Henan). As she neared death in 274, she feared that whoever would be empress next would endanger the crown prince status of her developmentally disabled son, Sima Zhong. Yang June, as the empress" father, became an increasingly important official in government, and became exceedingly arrogant.
As Emperor Wu grew ill in 289, he considered whom to make regent.
As a result, Yang June became fearful of Sima Liang and had him posted to the key city of Xuchang. Several other imperial princes were also posted to other key cities in the empire.
By 290, Emperor Wu resolved to let Yang and Sima Liang both be regents, but after he wrote his will, the will was seized by Yang June, who instead had another will promulgated in which Yang alone was named regent. Emperor Wu died soon thereafter.
Crown Prince Zhong succeeded to the throne as Emperor Hui.
Yang June became Emperor Hui"s regent, and became much criticized for spending his energy on making himself secure—including not attending Emperor Wu"s burial. Yang knew that he had made a lot of enemies, and tried to pacify them by giving widespread promotions, but those promotions only served to show his weakness. Empress Jia, who wanted her hand in governance, was dissatisfied with the situation, and conspired with the eunuch Dong Meng (董猛) and the generals Meng Guan (孟觀) and Li Zhao (李肇) against the Yangs.
She tried to include Sima Liang into the conspiracy, but Sima Liang declined.
Instead, she persuaded Emperor Hui"s brother, Sima Wei the Prince of Chu, to join her plan. In 291, after Sima Wei returned to Luoyang from his defense post (Jing Province (荊州, modern Hubei and Hunan)) with his troops, a coup went into progress.
Quickly, it became clear that Yang was in trouble, particularly after he declined his strategists" suggestion to burn the palace gate to temporarily halt the advance of the imperial guards. Empress Dowager Yang, trapped in the palace herself, wrote an edict ordering assistance for Yang June and put it on arrows, shooting it out of the palace.
Empress Jia then made the bold declaration that Empress Dowager Yang was committing treason.
Yang June was quickly defeated, and his clan was massacred.
