House Lannister is one of the Great Houses of the Seven Kingdoms and the principal house of the Westerlands. Its seat is at Casterly Rock. Its coat of arms displays a golden lion rampant on a crimson field, and its words are Hear Me Roar! More famous than its official motto is the House’s unofficial one: A Lannister always pays his debts. The Lannisters ruled as Kings of the Rock until House Targaryen invaded Westeros. They are the richest family in the Seven Kingdoms because of the gold mines located on their lands. They are the main antagonist of the series.
Before the events of the series, Tywin Lannister was robbed of his heir when King Aerys II Targaryen appointed Jaime Lannister to the Kingsguard. In protest, he resigned from his position as Hand of the King. When Robert Baratheon rebelled, Tywin remained neutral until Robert’s victory was certain. He then moved to capture King’s Landing. As the city was invaded, Jaime murdered Aerys, allowing Robert to claim the throne. Robert then married Jaime’s twin sister Cersei.