Aerys II Targaryen, also known as the "Mad King," was the last Targaryen ruler of the Seven Kingdoms of Westeros. He reigned from 262 AC until his overthrow in 283 AC during Robert's Rebellion. Aerys was known for his erratic behavior and cruelty, which led to widespread fear and unrest among his subjects. His reign was marked by increasing paranoia and violent outbursts, including the infamous execution of his enemies. Aerys II's downfall came when he ordered the execution of Ned Stark, which prompted a rebellion led by Robert Baratheon. His death marked the end of the Targaryen dynasty's rule in Westeros.