- "Do you remember the taste of the water? Recycled so many times it could never be made pure again? ... Do you remember the taste of metal in the air? The stink of 20,000 souls crammed into a shelter designed for half that number?"
- ―Philip Pearson
At an unspecified point in time, human civilization has all but collapsed and the survivors live in squalid, disastrous conditions. This necessitated the Grand Plan and the Traveler program to correct the mistakes of the past.
In an alternate version of 2018, an asteroid designated Helios-685 collided with Earth, killing over 63 million people. The impact resulted in massive tidal waves; Philip Pearson uses the simile "like a Helios tidal wave" to describe emotion reaction to a drug overdose in Room 101. The Director's initial version of the Grand Plan was centralized around preventing the impact, which the Travelers accomplished.
A chemical compound designed to combat heroin addiction is invented at some point in the late 2030s.
Anna Hamilton is elected 53rd President of the United States by a slim margin; her opponent is described by Grant MacLaren as "another old white guy" (who in fact wins the election in an alternate timeline). The country is said to have been torn apart by the election. Anna is eight years old as of 2017, therefore it is assumed that the election could not have been sooner than 2044 if the age requirement for President set by the United States constitution has not been altered in the future.
In 2068, Robert Fraser discovers a new element which proves essential to the creation of a room-temperature superconductor used in quantum computing.
The exact year in which the Traveler program began is never stated outright, merely that it is centuries from the present day. Travelers seldom discuss the future, as they are forbidden from doing so according to Protocol 2.
- "The ozone layer is gone by then. That's just one problem. In a hundred years things are way worse. We live under the ice. Oh, the math's not that complicated. You have two people that want the same thing, the two people fight over the one, and then there's none."
In an alternate version of 2017, the corporation Galston Agriculture developed seed-C589, a genetically modified seed designed to extract more nutrients from the soil. C589, which contains genes from the kudzu weed, became the cause of widespread famine when it spread and rendered large portions of land untenable.
Further environmental consequences resulted from the proliferation of antimatter weapons. Simon claims that the Earth's ozone layer has disappeared in the future and a new ice age has begun.
- "Maintenance of the yeast vats, first and foremost, is your responsibility to the community."
Due to the volatile environmental conditions, humans have abandoned the towns and cities of old to live in bunkers, of which there are at least forty-one. These bunkers are located in a mountain range on the former United States-Canada border. The enclosed spaces, which were only designed to accommodate 10,000 people but which may contain twice as many, necessitate communal living.
The surviving humans are ruled by an advanced quantum artificial intelligence known only as the Director. The Director controls "every facet" of people's lives, akin to a dictator.
An unnamed faction is in open rebellion against the Director. At one point they succeeded in deactivating the Director and seized partial control of the time travel program. The Director was subsequently restored to power, literally and figuratively, due to the intervention of the core traveler team.
Despite the collapse of society, humans have still managed to innovate and invent technologies that would seem alien or even magical to a modern person. Most notable is the Director's ability to send data - including human consciousness - back in time via quantum entanglement.
The Traveler program was made possible with the development of consciousness transfer, the ability to send a mind into a different body. Trevor Holden was one of the first volunteers for this program, and Simon claims to have helped build the original transferal machine.
The technology has its limits. Consciousness transfer requires a T.E.L.L., and global positioning systems did not become accurate enough to prevent misfires until the early 21st century, effectively prohibiting time travel to earlier eras in human history. Furthermore, it is impossible to send a traveler or message further back in time than the arrival point of the most recent traveler or message.
Modern medicine is essentially obsolete in the future, replaced by nanotechnology. Programmable machines called nanites are used to heal wounds and cure diseases. The Director only authorizes their use in the past in extreme emergencies, however, so every traveler team has a medic who is specifically trained in 21st century medicine.
While the Director itself is powered by nuclear fission, a contemporary technology, humans have nonetheless developed alternative energies in the future. Antimatter development began in 2016 as an alternative energy and evidently became the cause of an arms race. Traveler communications devices, called "comms" for short, are powered by the energy in the human body.