Occuring in 270AL, The Defiance of Duskendale was a pivotal event that is believed to have caused King Aerys II to go crazy and earn his nickname as the Mad King. When House Darklyn of Duskendale refuses to pay taxes to the Iron Throne, King Aerys II goes to Duskendale himself to handle the situation. Things take an unexpected turn and King Aerys is taken prisoner, where he is held captive for six months, until Ser Barriston Selmy rescues him. It is believed that six months of captivity turned King Aerys mad with paranoia, and despite being rescued, he was never the same. This event was also significant as it increased tensions between the Mad King and his Hand, Tywin Lannister, whom the Mad King believed did not put forth effort to rescue him.

King Aerys II, otherwise known as the Mad King, after being taken captive during the Defiance of Duskendale