"The Internationale will be the human race."

The United Socialist Republics of Earth are children of the Low Age. This social-democratic polity is the most populated entity in settled space, accounting for more than three billion citizens on Earth. It covers the African, European and Asian continents except for the east-Asian area. It is one of Earth's two "meta-states" that emerged at the beginning of the interstellar age. It is made of ten Socialist Republics themselves divided into one thousand and fifty-five polities of various sizes and types. Though it doesn't have any holdings beyond the Earth the Union has several coordination agreements with various planets and stations in Communal Space.

There are two ways of considering the USRE. Extraterrestrial polities tend to see the United Socialist Republics of Earth as a coherent superpower taking the shape of a state with well-defined borders, elected representatives and a wide array of other attributes that are reminiscent of those possessed by pre-interstellar age nation-states. Terrans, on the contrary, do not see the USRE as a state. To them, the USRE is the framework within which thrive the thousands of communes, cooperatives, substates or federations existing on USRE-controlled territory. To most of its citizens, the USRE is a vague presence that exists through land planning grants, distant spaceships and continental parliamentary votes in the Socialist Republics.

In truth the USRE is both a vague federation and a quasi nation-state: the difference is only a matter of scale. At an interstellar scale, local planetary cultures or polities are blurred together and the USRE appears as a coherent state. At a sub planetary scale, however, these cultures are all that matters and the USRE is just an overarching structure that cannot possibly grasp the sheer complexity of a society with three billion members. This incoherence is only apparent: it comes from interstellar perspectives clashing with the staggering diversity of the Earth.

The USRE is not rooted in any specific ethnicity or pre-Low Age legacy. The Union, at heart, is a planning entity. Land planning, ecosystemic planning, urban planning, economic planning, military coordination, off-world diplomacy. It is a strength multiplier for the entities that fall under its umbrella, bringing and leveraging resources to create and coordinate at a quasi-planetary scale. This achievement should not be understated: in terms of population, the USRE is the single biggest human polity in the known galaxy. The very fact that it did not collapse already is already an achievement in and of itself.

As far as non-Terrans are concerned the USRE is mostly known through the various administrations that represent the Union abroad and further its interests. USRE Solar Envoys operate within the Solar Council, which possesses its own ships. The Union projects hard power through the High Fleet numbering at almost two hundred combat vessels as well as the Low Fleet taking part in Flower Wars. Finally, the USRE maintains its own deep space exploration organisation known as the USRE Council for Interstellar Science.

The heavily interventionist USRE is not loved in the interstellar community. Many consider that it should mind its own business considering that the Earth is self-sufficient and does not need outside economic or demographic support. However, the Union considers that it has a moral duty to support and protect the first colonies that directly descend from Earth-bound settlers. It sees places such as Trappist or Tau Ceti as its objective allies much to the despair of local independent polities. The Moon Communes  in particular have yet to end their centuries-long feud with the USRE over shipbuilding rights.

ADDENDUM -- USRE Infographic