So, when I first got in to the Institute I managed to convince myself that they were formed from the remnants of Vault-Tec. Numerous mentions are made to how the Institute started, but none of them that I noticed seemed to contradict the idea.

Is this a possibility? Or are there vast sections of Fallout lore that would specifically rule this out?

Well, vault tec was a company, with a HQ and office buildings and such. There is no reference to them that I have found that says they were a university or other such establishment.

The underground Institute was formed by the remnants and survivors of the CIT above it, which was a school. It might be possible that Vault tec controlled the CIT or something but I haven't seen anything to support that.

They do have similarities like they both built huge clean structures underground like all of the vaults and the Institute labs and they both love experimenting like in all of the vaults and the FEV labs and Synth production but the institute was comprised of scientists who went under ground where as Vault tech is a company that made vaults across America so maby Vault tech helped the institute make their giant underground fasility because it would be a huge undertaking to make but they just don't say. So I suppose it is up to conjecture and assumptions with no evidence supporting or denying it.

The underground facility was made many years after the war, it wasn't made beforehand. I have no idea if vault tec survived the war and in what capacity but there is no mention that the institute had any outside help.

There is no real evidence to support. Vault-Tech was a company and the CIT was basicly the MIT.

It is however likley that at least a few people in the CIT knew about vault-tech's experiments since it not that uncommon to have at least someone from a learning institution work on big projects in one way or another even today. Given the importance of any scientist due to needing everyone halfway qualified during the war and how many vaults were created I'd say it is not only likely but almost guaranteed that some people have a connection to vault-tech and some "inspiration" could have flown.

BUT we also have to consider the general lack of morals in many important pre-apokalypse organsations such as the researchers in the BIG MT. So the institute might have just preserved their attitude from before the war independant from vault-tech.

I have found 1 reference in vault 81, where it is said that vault-tech should return with gathered informations to the university. I didn't play fallout 1,2, so I started to be curious also, what is this vault-tec and the university and how is it all connected. I thought it was all military made.

It is possible that vault tec hired their scientists from local universities. They needed people to run the experiments and I don't think they used vault tec employees for all of that. The hired the overseers and staff from the local area. Still interesting, I will have to find that vault and investigate.

If vault tech did help create the institute hQ then surely the hq would have even more questions , because we all know vault-tech is hella shady

I found another one:

http://fallout.wikia.com/wiki/Robert_House

House attended the http://fallout.wikia.com/wiki/The_Institutey and later founded RobCo Industries who helped to construct vaults together with vault-tec for the goverment.

http://fallout.wikia.com/wiki/Vault

I'm not sure how important it is, but it is atleast something

But that was after he was finished. It is not known if he had any ties to the CIT after his graduation.

really? How in the world did they get all the manual labor needed to dig out such a huge amount of space and have all the dirt alone assuming their was no bed rock just vanish off the face of the earth especially so close to the Boston river, it must have been a feet of engineering just to keep it from flooding and it does not explain how they survived the bombs or the fallout that dispersed only enough to breath outside after atleast 25 years if they were not underground than where were they? On the surface?

The Institute was formed from faculty, staff, and students of the Commonwealth Institute of Technology. They took shelter in the College's lower basemant during the Great War and afterwards gradually began digging out an underground environment to leave in.

CIT was unaffiliated with Vault Tec. Vault Tec was a private pre-war corporation, while CIT was a https://en.wikipedia.org/wiki/Massachusetts_Institute_of_Technology.

But if the Institute wasn't connected directly, they could be atleast "spiritual" predecessor. Something like a mother of all evil scientists, a nest of all experiments ideas, students brainwashed by evil wise looking professors, then released into government and military and thus somehow connected to Enclave and Vault-tec the same way as dr. House RobCo Industries was

Vault-Tec was by and large just doing the bidding of the U.S. Government.

People seem to forget that essentially the entirety of Fallout's ills were the progeny of the completely immoral pre-war U.S. Government. The societal preservation experiments, the FEV program, deathclaw genetic research, kill-bots, and (to a certain extent) nuclear holocaust itself. And the Sino-American war is what sparked most of these creations. As they were all attempts to defeat outright, or out-survive the Chinese.

Hell, even The Enclave, their successors, don't have a high-opinion of the pre-war administration. President Eden calls them incompetent idiots.

oh so they "hid in the basemant" like you would in a tornado and had enough sientists without any construction experiance or tools for digging or keep dirt from collapsing in on them and with no supply of lumber or steel for supporting it or for making air vents so they could breathe underground were able dig that giant structure under ground and the dirt magically vanished, how convinent.

They had lots of robots you know?

let me tell you even if they broke down all of the robots that could fit in that CIT building they still would not have enough steel to keep that giant hole in the ground from collapsing in on itself and getting flooded by the Boston river.

If you go the minutemen ending you will see there was already a large drainage system under CiT to move water out/around from before the war.

they still use it to this day, and the tunnel also serves as the only means to get into The Institute, except via teleportation.

OK that would keep it from flooding before it collapses but would not stop it from flooding if the dirt collapsed in on itself like when you blow it up and it becomes a giant water filled crater.

http://engineering.mit.edu/

Plus if I recall correctly, there's a terminal somewhere on the CIT campus which mentions funding for an underground project being allocated by the school administration. So some of the construction may have begun already before the war.

But regardless, Vault Tec wasn't involved at all.

the funding may have been used to pay Vaultec to build it because they have experience in making under ground structures from all the vaults they made silly or at least to put in the supports for the structure if nothing else which would have kept it from collapsing.

Or not.

You know, because MIT has its own advanced engineering and architecture department.

Honestly, why the hell would they need Vault-Tec? Its not like Vault-Tec has a monopoly on underground bunker-like structures. And certainly nothing in-game hints at any sort of cooperation between them and CIT.

The CIT should be more than capable of building their own underground structures. They maybe have shared the same personal because it is practice to do so even today but there is no indication that vault tec made anything in the institute. They use different architecture, there are no terminals with clues about that and no vault tec logo is found to be found inside of the institute.