Item from A Song of Ice and Fire by George R.R. Martin
A Valyrian steel longsword forged from the remelted Ice — given by Jaime Lannister to Brienne of Tarth as both a weapon and a promise to protect the Stark girls.
Oathkeeper is a sword at war with itself — Lannister gold and Stark steel, given as an act of honor by a man the world calls dishonorable, wielded by a woman most knights refuse to acknowledge. When Jaime gave it to Brienne and named it Oathkeeper, he was doing something the Lannisters almost never do: keeping a promise. She was to find and protect Sansa Stark, and the sword was proof of intent. Every time Brienne draws it, the blade tells a story about the gap between reputation and reality — Jaime's oath to Catelyn Stark, Brienne's oath to Jaime, and the Stark steel serving a cause the Starks would have approved of, even if they'd never trust the family that forged it.
A longsword of Valyrian steel with ripples of red and black running through the blade — the steel took on a crimson tinge when reforged, as if the metal remembered the Lannisters' intentions. The hilt is gold, set with a lion's-head pommel and rubies. The scabbard is red leather.
Also known as: Oathkeeper, Brienne's sword