The Rains of Castamere - a Game of Thrones cover

"The Rains of Castamere" is the theme song of House Lannister, in the tv show Game of Thrones. The song is about a vassal house, House Reyne of Castamere, rebelling against House Lannister. See Tywin Lannister, the eldest son of the current Lannister lord, led the Lannister forces to Castamere and obliterated House Reyne. Like House Lannister, House Reyne's sigil was a lion but red instead of gold, thus the rebellion was called a civil war of lions.
Throughout the show, the song and theme of Rains of Castamere is played when the Lannisters are gaining the upper hand against their enemies.