The Battle of the Golden Tooth was the opening battle of the War of the Five Kings.
Ser Edmure Tully had sent Lord Clement Piper and Lord Vance to guard the pass at the Golden Tooth, to prevent any Lannister army from entering the Riverlands. Ser Jaime Lannister, commanding the Lannister forces, descended on the Riverland army and broke them. Lord Vance was slain during the fight. Lord Piper retreated back to Riverrun with the remnants of his forces, with Ser Jaime following him. During the battle, Lord Tywin Lannister was able to bring another Lannister army up from the south.