The cabinets in Captain Georgiou's ready room are filled with props that contain Easter eggs, but most are too difficult to make out in during the show. Behind the scenes photos reveal a bottle of 2249 Château Picard wine, Starfleet medals previously awarded to Jonathan Archer and James T. Kirk and a diploma from an Andorian military academy. The books on these shelves all feature Star Trek (1966) episode titles including The Cage (1966), Balance of Terror (1966), The City on the Edge of Forever (1967), Amok Time (1967), Mirror, Mirror (1967), Metamorphosis (1967), The Deadly Years (1967), The Trouble with Tribbles (1967), Return to Tomorrow (1968), Patterns of Force (1968), By Any Other Name (1968), The Omega Glory (1968), Plato's Stepchildren (1968), The Empath (1968), Whom Gods Destroy (1969), The Mark of Gideon (1969), That Which Survives (1969), The Way to Eden (1969) and All Our Yesterdays (1969).
As Burnham subsequently relays to Georgiou, Sarek explains that the disastrous first contact between Vulcans and Klingons occurred 240 years ago in the H'atoria system. That system was previously mentioned in All Good Things... (1994) as the site of a small Klingon colony near Federation space. In the alternate future timeline seen in that series finale, Worf had become governor of the colony.
In this episode, Tasia Valenza took over the role as the Federation computer voice, a role Majel Barrett-Roddenberry, Majel Barrett, held from 1966 until her death in 2008.
While the Klingon death ritual in this episode has some new elements to it, the long-established death howl makes an appearance during Rejac's funeral: the Klingons gathered for the funeral howl not out of grief, but to warn the honored ancestors in Sto-vo-kor that a worthy Klingon warrior is coming to join them. The death howl was first established in Heart of Glory (1988).
The scene in which Burnham renders Georgiou unconscious with a Vulcan nerve pinch is not the first time a non-Vulcan has used the technique. Other people who managed to employ a Vulcan nerve pinch include Jonathan Archer in Kir'Shara (2004), Jean-Luc Picard in Starship Mine (1993), Data in Star Trek: Nemesis (2002), Odo in Paradise Lost (1996), and Seven of Nine in The Raven (1997).