Rednog said:
Ohhh that's really cool, tying the games together like that.
As for the story-line, Rapture was indeed already in the crapper before the 1959's New Year's Eve event. You can make that out from the craploads of audio diary's you find. Ryan started to feel threatened, that his he felt his city and principles become threatened, when Fontaine started to become really big.
Shit really started hitting the proverbial fan when he thought he took Fontaine down. After that, Fontaine re-emerged as Atlas and started a campaign against Ryan. From that point on, things became more and more grim in Rapture. Ryan started police actions to combat the rising insurgents and Atlas' men became more and more aggressive each day (and destroying themselves by weaponizing their own bodies with plasmids in the process) as well. Then on New Years Eve, the already existing tension exploded into full-blown civil war which is what the multi-player section in BioShock 2 is supposed to be.
That civil war raged on for about a year (hence, the 1-40 track took 1 in-game year, so to speak), destroying the already weakened city. People either got killed or joined up with one of the camps, becoming a ravaging Splicer you see ingame, hence the near-total lack (you see one pretty-much regular guy getting killed off in the beginning of BioShock 1, and there is of course Ryan, Fontaine, Sinclair, Grace, etc) of a regular civil population.
And thus you end up with the awful Rapture you enter in BioShock 1. Now sadly I can't put years on the events preceding the 1959 New Year's Eve disaster, so I can't make it more accurate than I made it already, but I think it paints a pretty clear picture. My guess is that Rapture sailed relatively smoothly for about 5 years or so. After that Fontaine became on the rise, splicing became mainstream, people started degenerating and Ryan became worried and thus signs of failure were starting to arise. After Fontaine's 'death', the roller-coaster started, and my guess is that it took about 2 years to get to the 1959 eruption. Add another year of horrid civil warfare, and voila, Rapture is kaput. But everything past the actual events is just speculation, I don't think that there is an official time-line (yet).