Why Bran and Arya's Mysterious Dagger Is Key to the End of 'Game of Thrones'
It finally happened. The Catspaw Dagger, a Valyrian steel blade reintroduced in Game of Thrones Season 7 that was destined to serve some essential purpose after having first shown up in Season 1 as the blade a hired assassin used to try to kill Bran Stark, fell into the right hands. Arya Stark's hands, that is. After Melisandre reminded her of an all-important prophecy that Arya would shut many eyes (including blue ones!), the young Stark rushes out of the castle to hunt down the Night King and save the day. No big deal for a girl with a famous name.
If you're having trouble remembering the full backstory of the dagger that turned the Night King into shards of icy glass, here's everything you need to know.
Game of Thrones Season 7 was a full shift up from how the HBO fantasy series worked in the past. The big surprise was that, after the fourth episode of the season, "Spoils of War," we have Sansa, Arya, and Bran, who haven't been together since the very first episode, back at Winterfell, and with them is Littlefinger, bringing an object that turns out to be a keystone in the grand narrative: the Catspaw Dagger.
The backstory of the dagger
The Valyrian Steel dagger that Littlefinger gave to Bran is referred to as the "Catspaw Dagger" because it hasn't been given a name yet on the show. The word "catspaw" refers to "a person used to serve the purposes of another," willingly or unwillingly, and in this case references the person who attempted to murder Bran in Season 1 ("The Kingsroad"). The catspaw lit a fire to lure Robb Stark away from Bran's room, but Catelyn stayed and fought off the assassin, injuring her hands on the dagger. Then, Summer the direwolf came in and chewed on the guy's throat, saving Bran and Catelyn. This incident introduced this specific dagger to the Thrones story, leading to the nickname the "Catspaw Dagger."
Whoever hired the assassin equipped him the dagger, indicating that the shadow wasn't high born and couldn't afford a Valyrian Steel weapon. The question of the blade's owner led Catelyn Stark to King's Landing, where Littlefinger admitted the dagger was his -- until he lost it to Tyrion Lannister in a bet. This leads Catelyn Stark to arrest Tyrion at the inn at the Crossroads, in part kicking off the War of the Five Kings.
In Season 4, we learned that Littlefinger set all the conflicts in motion by having Lysa Arryn poison her husband Jon Arryn (before the first episode) in an effort to incite war between the Lannisters and Starks. The dagger hasn't been seen since it was on Ned Stark's desk in Season 1, Episode 4 ("Cripples, Bastards, and Broken Things"). Littlefinger snagged it after betraying him.
What the books tells us about the mystery
In the A Song of Ice and Fire books, there isn't a definitive answer about who sent the catspaw after Bran in Winterfell. There is a better answer than the show ever gave us. While Jaime Lannister is a Stark prisoner after the Battle of the Whispering Wood, he admits to pushing Bran out of the window, but denies trying to have the boy killed. As evidence he points out that Littlefinger said he lost the dagger to Tyrion betting against Jaime in Joffery's Tournament, but Tyrion would never bet against Jaime in a tournament (in the show this doesn't happen). Jaime recalls that the Littlefinger lost the dagger in a bet, but to King Robert Baratheon, not Tyrion.
Later, in the novels, when King Joffery received the Widow's Wail, his Valyrian Steel sword, he mentions being "familiar with Valyrian Steel," which leads Tyrion to suspect that it was actually Joffery who attempted to have Bran killed as a misguided way for the sociopathic child to impress Robert, who he thought was his father. Being a Baratheon in name, Joffery would have had access to the dagger and was in Winterfell at the time the assassin would have been hired. Tyrion shares this suspicion with Jaime when he's escaping the Black Cells (after Tyrion's trial for Joffery's murder) and Jaime agrees with him, suggesting that -- from George R.R. Martin's perspective -- we should consider Joffery the prime suspect in the attempt to murder Bran. The show seems uninterested in answering that question since the dagger has been missing for several years… until Season 7!
What role the dagger plays in the show
The dagger's chain of ownership -- from Littlefinger to Bran to Arya Stark -- told us that the dagger was going to play an important part in the future of the show. Ever since the dagger and Baelish had been in the same place, the dagger was a symbol that Littlefinger's working against the Starks. In the first season, he used it to imprison Ned. Season 7's scenes had Littlefinger using the gift as a way of failing to manipulate Bran. The dagger pops up again with the three Stark children, prompting Sansa to question Littlefinger's motives. Then Arya uses it to spar with Brienne, a silent power shift between the two Stark girls that Littlefinger wants to use to his advantage, at least before that backfires and Arya slits his throat with the catspaw. The dagger's presence means Littlefinger was working against the Starks, yes, but what if the answer to Bran's question, about who owned the dagger in the first place, isn't "Littlefinger," but "Jon Snow"?
The dagger first popped up in an unexpected place: as an illustration in an old book in the Season 7 premiere, "Dragonstone," when Samwell Tarly is reading a book about the Long Night (i.e. the last time the White Walkers came), discovering that there is a mountain of obsidian under Dragonstone. While he's reading, we catch a glimpse of what appears to be the Catspaw Dagger on one of the pages. On that page we can see the following text:
The Valyrians were familiar with dragonglass long before they came to Westeros. They called it "zirfyl perzfyl" [sic] which translated to "frozen fire" in Valyrian and eastern tales tell of how their dragons would thaw the stone with dragonflame until it became molten and malleable. The Valyrians then used it to build their strange monuments and building without seams and joints of our modern castles.
When Aegon the conqueror forged his Seven Kingdoms, he and his descendants would often decorate their blades with dragonglass feeling a kinship with the stone. The royal fashion for dragonglass ornamentation soon spread throughout the Seven Kingdoms to those wealthy enough to afford it. Hilts and pommels were and are the most common decoration for dragonglass if too brittle to make a useful crossguard. Indeed, its very brittleness is what relegate it to the great houses and the most successful merchants.
This connects the dagger, which we already knew was Valyrian steel, to a deeper history of Westeros (beyond it being used to try and kill Bran). In "The Spoils of War," Bran wonders who owned the Catspaw Dagger, and the show pretends that the only way to take that question is "don't you remember this dagger," when the Three-Eyed Raven was probably asking a much bigger question. A Valyrian steel-forged dagger, as Sam's book points out, is for the Great Houses like the other Valyrian Steel in Westeros... so how did it end up in Littlefinger's hands before the series began? Baelish owns no castle and made up his own House all for himself, the dagger wasn't handed down to him by any legitimate means.
Now we know that Baelish's possession of the dagger was just a means to the end of having it wind up in Arya's hand. During the Battle of Winterfell, after wights destroy the cool double-spear weapon Gendry made for her, Arya still hangs on to the weapon, knowing (thanks to Melisandre) how she has to use it. Just when it looks like the Night King has stopped her charge at the Godswood, though, her assassin training pays off -- she drops and catches the Catspaw in her other hand and jabs it into the undead leader, shattering him and his entire army, saving Winterfell and the living in the process.
So, yeah: The Catspaw Dagger turned out to be super important, just as we suspected. Now we'll see if Arya gets to use it against Cersei and her troops as the battle for the Iron Throne returns to its full force.