From A Wiki of Ice and Fire
Castamere is a ruined castle located south of the Crag and west of Ashemark in the Westerlands; also nearby is Tarbeck Hall. The former seat of House Reyne, Castamere contains gold mines.
Following the failed Reyne-Tarbeck Rebellion, Tywin Lannister extinguished proud House Reyne and shattered their castle. The fate of the Reynes and Castamere is remembered in the song "The Rains of Castamere".
A Clash of Kings
Lord Greatjon Umber captures the gold mines of Castamere after the Battle of Oxcross.
A Storm of Swords
For the part he plays in the downfall of House Stark during the War of the Five Kings, Ser Rolph Spicer is raised to lordship and House Spicer receives Castamere.
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