Short answers, pulled from the story.
The Jiajing Emperor, personal name Zhu Houcong, was the 12th emperor of the Ming dynasty, reigning from 1521 to 1567. Born on the 16th of September 1507, he was a cousin of his predecessor, the Zhengde Emperor, and came to the throne unexpectedly after the Zhengde Emperor died without an heir.
The Great Rites Controversy was a political dispute at the start of the Jiajing Emperor's reign over whether he should be legally adopted as the Hongzhi Emperor's son in order to legitimize his claim to the throne. The Emperor refused adoption, insisting instead on honoring his biological father with imperial rank. After three years of conflict, 17 opposing officials died from wounds received at court, and the rest were exiled to the provinces.
The Jiajing Emperor moved to the West Park of the Imperial City in 1542, following an assassination attempt on the 27th of November of that year in which palace women tried to strangle him with a silk cord. He was drawn to the site's Taoist associations and constructed it as a complex of palaces and temples where he could pursue immortality. He never returned to the Forbidden City after 1542.
Taoism was central to the Jiajing Emperor's personal life and influenced his governance from the beginning of his reign. He patronized Taoist adepts including Shao Yuanjie and Tao Zhongwen, had temples built at considerable cost using timber transported from distant Sichuan, and consumed alchemical elixirs containing arsenic and mercury in pursuit of immortality. After 1545, he relied on Taoist oracles organized by Tao Zhongwen for guidance in state affairs.
After Altan Khan unified the Mongols in the 1540s, repeated raids struck Ming territory because the Jiajing Emperor refused to restore trade. Mongol forces plundered Shanxi in 1541-1543, attacked the vicinity of Beijing in the late 1540s, and reached the city walls in 1550. The Emperor briefly opened border markets in spring 1551 but closed them after six months, and raiding continued across the northern frontier for the rest of his reign.
Groundnuts, sweet potatoes, and maize all reached China during the Jiajing era. Groundnut cultivation was documented in Jiangnan in the 1530s, having spread from Fujian where peasants received the crop from Portuguese sailors. Sweet potatoes appeared in Yunnan at the start of the 1560s via Burma. Maize cultivation was recorded in inland Henan as early as the 1550s, though it would not be widely grown in Han-populated regions until the 18th century.