Answer
The assassination of Dong Zhuo, the ambitious warlord who controlled the Han imperial court, took place in 192 CE. Lü Bu, a skilled warrior and one of Dong's subordinates, turned against him due to personal grievances. With the help of a fellow officer, Lü Bu ambushed Dong as he was leaving the imperial palace in the capital, Chang'an, and successfully struck him down, ending Dong's tyrannical grip on power.