"And so ended both the reign of House Targaryen and Robert's Rebellion—the war that put an end to nearly three hundred years of Targaryen rule and ushered in a new golden era under the auspices of House Baratheon."
Maester Yandel
Robert's Rebellion, also known as the War of the Usurper, was a rebellion against House Targaryen under Aerys II Targaryen, primarily instigated and spearheaded by House Stark, House Baratheon and House Arryn. It lasted nearly a year, but the civil war tore the kingdoms apart, with few houses declaring for House Targaryen, while the majority fought for the powerful Lord Robert Baratheon. Primarily triggered by the kidnapping and raping of Lyanna Stark and the execution of Rickard and Brandon Stark, the war resulted in the fall of the Targaryen dynasty, the death of the Targaryen royal family, and the beginning of the Baratheon dynasty, under Robert, who seized the Iron Throne for himself. It ended three hundred years of Targaryen rule in Westeros, and saw a complete shift in the political atmosphere of the Seven Kingdoms.