Homeworlds/governmental capitals are listed first in each region.
The Republics are collectively the galaxy's most powerful economy, and carry enormous weight in trade and diplomatic circles. Republican worlds, and the Republics as a whole, have no politicians (the Citadel Councillor being an exception); political authority is vested directly in the citizenry as a whole, via global communications networks allowing all citizens to participate equally in policy debates. The Republics suffered extensive damage from Reaper attacks, and their ties with allies were strained by their inaction early in the conflict; rebuilding programmes underway focus on ensuring long-term economic stability.
The Hegemony was a totalitarian state, which included a caste system that permitted the forced enslavement of non-batarians, as well as slave-caste batarians. When part of the Citadel governments, the Hegemony was involved in a number of disputes with its fellow members; the final straw was the Council siding with the Systems Alliance in its disputes with the Hegemony, after which the Hegemony sealed its borders and went into self-imposed exile. The Hegemony was virtually annihilated by savage Reaper attacks, and the surviving populations are now rebuilding and, in the old government's absence, redefining their political identities.
- Gorash (disputed)
- Lorek - originally the asari colony Esan, annexed by the Hegemony.
The elcor government is known as the Counts of Dekuuna. Elcor politics are heavily dependent on the recommendations of the Elders, who extensively consider precedents and hypothetical scenarios in order to provide clear guidance for their people; given sufficient knowledge of these records, elcor politics are likely to be highly predictable. Elcor colonisation efforts favour high-gravity worlds that mirror their homeworld.
The Primacy is the overall government of the hanar species. Following the evacuation of their homeworld, the surviving drell are primarily settled in hanar space. The Primacy is somewhat isolated from its fellow Citadel members, but its scientific contributions are impressive. It is theocratic in nature.
Following their participation in the Reaper War, the krogan have been cautiously welcomed back to galactic society as a free and self-governing society. After centuries of the genophage and Council restrictions limiting the krogan, many view their newfound freedom with concern.
The Migrant Fleet, or Flotilla, was the home of the quarian people following the geth uprising. Individual populated vessels are listed. Following the peaceful settlement of the quarian-geth conflict during the Reaper War, the majority of the Flotilla's population is making the transition to living on Rannoch; many vessels remain in service, and some have even elected to continue their nomadic lifestyle.
The Salarian Union is a collection of political units united by a labyrinthine web of alliances and familial relations; each unit (which translate to fiefdoms, baronies, duchies, planets, and marches) is ultimately ruled by a Dalatrass. While largely spared the destruction suffered by other regions during the Reaper War, the Union's inaction in the conflict has resulted in significant internal political unrest and external diplomatic tension.
- Farish Vey
- Gorot II
- Ipsen Slator
The Alliance is a representative body, formerly controlled by a parliament based at the Alliance capital of Arcturus Station. It had the backing of Earth's most powerful individual nations, and acted on behalf of Earth and the majority of human colonies in the galaxy, although a number of human colonies have chosen not to become Alliance members. Following the Reaper War Earth is under temporary military administration due to the near-total destruction of its civilian governments, and significant tension now exists between Earth and the human colonies, who are relied upon heavily to supply the rebuilding efforts on the homeworld. The Citadel's relocation to Earth orbit, and the Sol relay's new position as the central nexus of the galactic network, have also greatly altered the political position of the Alliance.
- Arcturus Station (destroyed by Reapers)
- Earth (homeworld)
- Eden Prime
- Terra Nova
The independent star nations and colonies of the Terminus Systems have no recognised central authority, although the space station Omega serves as a de facto mercantile capital. Although suffering extensive Reaper attacks, and subsequent divisive infighting, the Terminus Systems maintain their independence and overall political weight, aided by a sharp increase in Omega's economic fortunes.
- Boro (volus colony)
- Erinle (salarian colony)
- The High Republic of Orozvhad
- Illium (asari colony)
- Rainreaved Ocean
- Sidewinder Colony
- Thunawanuro (elcor colony)
- The Vonskar Coalition
- The Wreck
- Tangeal Expanse (Cluster)
- Yomuuk Belt
The turian government is a hierarchical meritocracy, sustained largely by turians' socially-ingrained traditions of personal responsibility and civic duty. At the highest level, colonisation clusters are governed by Primarchs, but each level of government confines itself to its own affairs, trusting subsidiary levels to administer themselves. The Hierarchy is engaged in extensive post-war rebuilding, drawing on all its resources under central administration.
The Vol Protectorate is a client state of the Turian Hierarchy, which receives taxation and handled matters of foreign affairs. In exchange, the volus, who are physically unsuited to warfare relative to their galactic neighbours, enjoy the protection of the powerful Hierarchy military. The volus can be considered the architects of the current galactic economy, creating the "credit" standard currency, and continuing to monitor and balance the apparatus of interstellar trade.
- Gladus Prime - a planet owned by the Gladus corporation, home to a vast manufacturing complex.
- The Citadel - formerly located in the Serpent Nebula, now in Earth orbit.
- The Gruul Cluster
- Kal'Ala IV
- Nemean Abyss
- Nubian Expanse
- Parnack - the homeworld of the yahg.
- PF-2845 - star system.
- Rakhana - the drell homeworld, rendered uninhabitable by environmental pollution.
- Turvess - the homeword of the raloi.