- "Ser Arthur Dayne, the Sword of the Morning... led the attack on the Kingswood Brotherhood. Defeated the Smiling Knight in single combat."
- ―King Joffrey Baratheon
In the books
In the A Song of Ice and Fire novels, the title of "the Sword of Morning" is bestowed upon a member of House Dayne who wields their family's ancestral sword, Dawn, an incredible blade forged from the metal in a "fallen star". Dawn is not, therefore, Valyrian steel, though it has very similar properties of strength, sharpness, and light weight. Unlike Valyrian steel, Dawn's metal is pale as milkglass.
The title is not hereditary, automatically passed down to the current head of House Dayne. Rather, the sword Dawn is only held by a member of House Dayne who is considered worthy of the honor, after displaying immense skill at swordsmanship. Sometimes the head of House Dayne wields Dawn, but in some generations of the family it is held by a younger brother or cousin. In some generations, no member of the family is allowed to wield the sword at all, because it is deemed that none have proven themselves worthy. When a current "Sword of the Morning" dies, he does not pass Dawn down to his own children: instead it is brought back to Starfall castle, to wait for a new "Sword of the Morning" to rise again (which may take generations).
According to George R.R. Martin, the sword Dawn remains at Starfall during the War of the Five Kings, because no new Sword of the Morning has yet risen since Arthur Dayne died.