Between devil-worshipping serial killers [1] and murderous ghosts [2], American Horror Story: 1984 [3] is one wild ride to hell and back. It's definitely an installation that connects with past AHS seasons, although perhaps not as deeply as, say, Apocalypse [4]. The clearest callback right off the bat is none other than the character of Richard Ramirez [5], who was previously up to no good in AHS: Hotel. But 1984 also dropped subtle Easter eggs [6] here and there throughout its run. On top of that, many occurrences unfolded by the end of the season that make us believe that we're seeing the consequences of Apocalypse first-hand. Let's go through all of the ways that 1984 connects to past seasons, both concretely and, very briefly, theoretically.
Hotel: Richard Ramirez
The most obvious connection to a past season is Richard Ramirez [7], who appears in AHS: Hotel at James March's Devil's Night with other serial killers in 2015. But there's a plot hole if Ramirez is really the same character in both seasons. In AHS: Hotel [8], Ramirez had died in prison in 2013, as he did in real life. This doesn't sync up with the events of the ninth season, though.
In AHS: 1984, Ramirez is kept at Camp Redwood on a death watch by the ghosts, because he had escaped prison and made a pact with the devil. He was once resurrected at the camp in 1984, and the ghosts assume that he can zip in and out of Camp Redwood alive, so they vigilantly kill him whenever he wakes up. More on this later.
Asylum: Briarcliff Manor
In the special 100th episode, Margaret Booth [9] makes it out of Camp Redwood alive and has since become a real estate mogul. She now has a ton of money from flipping creepy, haunted places and keeps Trevor on a leash with her wealth. In a segment of Lifestyles of the Rich and Famous, we learn that Margaret owns Briarcliff Manor. This is a direct connection to Asylum, which also connects to past seasons such as Freak Show, Cult, and Roanoke. (Freak Show shows Pepper getting checked into Briarcliff, while Cult and Roanoke reference Lana Winters.)
Cult: Spahn Ranch
Margaret also happens to own Spahn Ranch, which was the primary residence of Charles Manson and his followers. Season seven [10], if you recall, features an episode where cult leader Kai Anderson tells his followers all about Manson (also played by Evan Peters) and his disciples. Linda Kasabian would eventually meet Manson at Spahn Ranch. Now, according to Margaret, little children frolic and eat funnel cake where Manson planned murders.
Hotel: John Wayne Gacy
Margaret definitely made bank, also acquiring John Wayne Gacy's ranch. If you recall, Gacy, also played by John Carroll Lynch (aka Mr. Jingles [11]), popped up at Devil's Night as Pogo the Clown.
Apocalypse (as Well as Murder House and Asylum): Satan/The Devil
The devil is more omnipresent than concrete, but he does get a shoutout throughout many American Horror Story [12] seasons. He's first a presence in Murder House, prompting the conception of Michael Langdon, who brings on the apocalypse in season nine. He also wreaks havoc on Briarcliff when possessing Sister Mary Eunice. In 1984, he resurrects Richard Ramirez from the dead.
Apocalypse: An Alternate Timeline?
This is by far the most speculative connection [13] but it's one worth considering. Basically, it makes no sense that Richard Ramirez stayed on death watch for 30 years at Camp Redwood if he died in prison in 2013 and made appearances for Devil's Night according to Hotel. But the one way that this could make sense is that 1984 exists in another timeline branch (yes, much like Avengers: Endgame), which could be a byproduct of Mallory using Tempus Infinitum and killing Michael Langdon in 2015 in Apocalypse. Or, you know, there was a plot hole.