Jon's decision to spare Ned Umber and Alys Karstark and allow them to keep their lands continues a theme started last season with Daenerys, namely the belief that children should not pay the price, nor bear the stain, of their parents' sins. However, Sansa's counter-argument that there is no punishment for treason, and no reward for loyalty brings up the discussion between being honorable versus pragmatic that recurs several times in both the novels and the series; Sansa has a point that doing the decent thing (i.e. showing mercy to enemies, breaking off a politically important alliance for love) was what got both Ned and Robb Stark killed. On the other hand, Joffrey's opportunistic execution of Ned also backfired, since it drew the ire of the entire North against the Lannisters.
When Jaime approaches Cersei in the map room, the mapmaker working on the floor is portrayed by Jim Stanes, the graphic artist who designed the massive map for the production.
Showrunners David Benioff and D.B. Weiss confirmed that because winter began in the sixth season finale, principal photography was pushed back from its usual July to December schedule to allow for seasons to change for exterior filming, and ultimately wrapped in late February. As a result, this will be the first season premiere of the series to debut in the summer rather than late March or April, which incidentally means the show will skip one year of Emmy eligibility.
While shooting the episode, Kit Harington got pranked by his fellow castmates, leaving him to believe that he accidentally tore his script and it was the only original.
Although Smalljon Umber was killed by Tormund Giantsbane in Battle of the Bastards (2016), the fate of Harald Karstark was not shown on-screen. This episode confirms that Karstark indeed died during the Battle of the Bastards. His death scene may have been scripted for that episode (which contained an unidentified Karstark cavalry man charging at Jon, only to be killed by Wun Wun), but time constraints may have forced production to abandon these plans. The last time Karstark was seen, he was leading the Boltons' cavalry, so it can be assumed that he died during the initial cavalry charge, or from one of Ramsey Bolton's subsequent arrow volleys.
Ed Sheeran: the popular singer plays the singing Lannister soldier whom Arya (Maisie Williams) meets in the Riverlands. Sheeran was finally able to make an appearance after he had been sought for a cameo for several years, since Williams is a big fan of his. His character is retroactively identified as "Eddie" in Winterfell (2019). In Red Notice (2021), Sheeran has another cameo where he yells at one point "I was in Game of Thrones!"