Quarian

The quarians are a nomadic species of humanoid aliens. They have no home planet and live aboard the Flotilla, a huge collection of ships that travel as one fleet.

Approximately three hundred years ago the quarians created the geth, a species of rudimentary artificial intelligences, to serve as an efficient source of manual labor. However, the geth gradually became sentient, rebelled against their quarian masters and drove them into exile. Now the quarians wander the galaxy in a flotilla of salvaged ships, secondhand vessels, and recycled technology.

Biology
Quarians are generally shorter and of slighter build than humans. They dress in a scavenged assortment of materials, hiding their faces behind visors, goggles, or breathing masks. Many people believe that the quarians are cybernetic, a blend of machine and biology that can survive for a time in the vacuum of space. Over the generations quarians' immune systems have atrophied due to the years in the sterile environment of the Flotilla. As such, quarians are always given various vaccinations and immunizations to help ward off disease. However, they still refuse to remove their suits as to not take the risk. Like turians, the quarians are a dextro-protein species, meaning the food of levo-protein races such as humans or asari could trigger a dangerous allergic reaction.

Politics
Humans don't have any political relations with the quarians because the Flotilla has not yet passed through any human-controlled area of space. Other species tend to look down on the quarians for several reasons. The most obvious is the geth; people condemn them for unleashing a dangerous synthetic life form on the rest of the galaxy. The creation of the geth was also grounds for the quarians losing their embassy on the Citadel.

Because of the Flotilla's limited resources, quarians strip-mine the systems they pass through, which often puts them at odds with any species currently settled there. The Flotilla also tends to drop off criminals on planets it passes, because the quarians can't support a non-productive prison population - they just don't have the resources. These factors have led to the quarians being seen as beggars and thieves. Tali says glumly that when she arrived on the Citadel, C-Sec hauled her in for a long interview before they let her wander around.

However, life on the Flotilla means quarians have unique skills. As Tali demonstrates, the quarians have developed an imperfect technique for recovering data from geth memory cores. They are masters at maintaining and converting technology, especially ship parts, and they are also expert miners because the Flotilla requires huge amounts of fuel. This proficiency means corporations sometimes hire quarians quietly on the side if the Migrant Fleet is nearby, replacing existing workers and making the quarians even more unpopular.

Culture
There are roughly 17 million quarians on the Flotilla (also called the Migrant Fleet). It is technically still under martial law but is now governed by bodies such as the Admiralty Board and the democratically-elected Conclave, though ship captains and onboard civilian councils tend to address most issues 'in-house' before it gets that far. Quarians are divided into several clans that can be spread across several ships, or restricted to one, but their names don't reflect which clan they belong to. A quarian's 'surname' refers to which ship they were born on, or, after their Pilgrimage, which ship they chose to join.

Quarians enjoy storytelling, and hold dancers in high esteem. Some ships from the Fleet linger in orbit over planets used as drive discharge sites, to sell refreshments, supplies or trinkets made by their children to passing crews. Young quarians go on a Pilgrimage as a rite of passage, leaving the Flotilla to look for resources, information or supplies that will be useful to the rest of the fleet. This discovery is presented to the captain as a gift upon the quarian's return. As well as proving they are a productive member of society, this ensures that the quarians maintain genetic diversity by not intermarrying with the crew of their 'home ship'. It is also seen as an opportunity for quarians to experience life outside the Flotilla, to appreciate their own culture. Tali says that though quarians spend their whole lives on the move, "we never leave home".

Insofar as religion goes, the quarians used to practice a form of ancestor worship. This involved taking a personality imprint from the individual and developing it into an interface similar to a VI. The quarians began experimenting with making these imprints more and more sophisticated, hopefully leading to the wisdom of their ancestors being preserved in an imprint that could be truly intelligent. After the geth became sentient and turned on them, some quarians saw their subsequent exile as punishment for this hubris, but most accept that the geth rebellion was a mistake, not a punishment.