I postulate that each former city had a survivor, with the sacrifice of a lover. This has obtained them a kind of immortality, at a price. The evidence proceeds as follows:
The Manager of the Royal Bethlehem is almost certainly a Polythreme native, which has been hinted to have been the first city. He lost his lover, who seems to be the original clay man, and is basically immortal, a glamour (broken when handing him a stone tentacle key) makes him appear younger. This love story led to the First Cities fall.
We know the Duchess is a daughter of the Pharaoh, and her lost love the Cantigaster. However, we can postulate she is somehow immortal, connected to the Hesperdarian Cider. We can postulate that by the fact that the cider is a beverage, a joint effort of Wines and Apples, and Wines has the closest ties to the Second City through his creation of the Vake.
Feducci is clearly immortal, as explicitly stated by the dueling storyline. We know he is from the Elder Continent, home of the Third City. This means he is either Snuffer Immortal, or, some other kind of immortality connected to the Elder Continent. I propose this could mean that he reached the Mountain of Youth. In addition, he is a member of the Dilmun Club, which is implied to seek immortality by their lapel pin sharing the symbol of the Hesperdarian Cider. His lost love is currently unkown.
Finally, the Gracious Widow is clearly a survivor of the Oriental Fourth City. I propose that this city is Xanadu, as more eloquently discussed in the Previous Cities thread. However, I further postulate that her widower, stated to be eve more ferocious, was Genghis or Kublah Khan. She is kept immortal through the use of the Brandy. The Brandy must be steadily taken, though. One dose is not enough to keep her immortal. In addition, it preserves her youth, unlike the Cider.
Together, these four unite the Gates of the Garden, and Falling Cities. Simply by the existence of four immortals tied to the four cities, such a line of reasoning is possible. So what do you think, everyone?