The War of the Usurper, more famously known as Robert's Rebellion in Game of Thrones, saw the coming together of four Great Houses - Arryn, Baratheon, Stark, and Tully to oust the ruling House Targaryen from power in Westeros. The uprising was against Mad King/ Aerys II Targaryen's tyrannical rule. It was sparked by Crown Prince Rhaegar Targaryen's alleged abduction of Lyanna Stark and the executions of the Lord of Winterfell, Rickard, and his heir, Brandon Stark. It consisted of a series of battles fought between the loyal and rebel forces on the territory of Westeros.