From A Wiki of Ice and Fire
|Battle of the Golden Tooth|
|Conflict || War of the Five Kings|
|Date || 298AC|
|Place || beneath the Golden Tooth, the Westerlands|
|Result || Lannister victory|
The Battle of the Golden Tooth was the opening battle of the War of the Five Kings and Lannister campaign in the Riverlands
Ser Edmure Tully finds out that the Lannisters are raising a host at Casterly Rock. He sends riders to the Rock, demanding that Lord Tywin proclaim his intent. Meanwhile he starts raising a host at Riverrun and sends Lord Vance and Lord Piper to guard the pass below the Golden Tooth, to prevent any House Lannister army from entering the Riverlands. Lord Tywin dispatches Ser Gregor Clegane to raid the villages along the Red Fork. Gregor somehow circumvents the Tully forces below the Golden Tooth. In response Ser Edmure further divides his forces, sending men to every village and holdfast with a day's ride of the border. Lord Eddard Stark fears this will weaken the defence of the riverlands. 
Not much is known much about the battle, but the attack seems to have been devastating. Ser Jaime Lannister, commanding the Lannister forces, descended on the Riverland army and broke them. Lord Vance was slain during the fight and Lord Piper retreated back to Riverrun with the remnants of his forces, with Ser Jaime following on his heels. During the battle, Lord Tywin Lannister was able to bring another Lannister army up from the south.
The rout of the Riverlands force beneath the Golden Tooth allows Ser Jaime to march on Riverrun, where he fought the Battle of Riverrun.
References and Notes