///From the author: the story of Rebirther is another one of many anthology tales within the Spacers Saga universe, inspired by such sci-fi classics as The Forever War and Starship Troopers. In the same vein of these stories of young men coming of age against a backdrop of military misadventure, Rebirther deals with the story of one Martian's time in Alpha Centauri during the vicious proxy war between the Martian Federation and the Solar Union, which forms a major part of the backstory of flagship Spacers Saga era INFINITUM. This document is intended to give a primer on the world Rebirther inhabits, so that anyone who picks it up someday will know what's what going in
The Story

(Art credit to Logan Stahl)
Focuses on Eduardo Alejandro “Eddie” Martinez - born in 2507 in Aldrin City on Mars, he joined MARSCOM in 2525 as part of the surge in patriotism which followed the outbreak of the Kuiper War; deployed to Alpha Centauri in 2527 after completing special operations training and served with standard spec ops for five years after arriving in 2531; in 2536 he was recruited into the Special Reconnaissance Task Force, and was a covert operative from 2537 on as part of Mars’ response to infiltration of the local government; saw service across the Rigil Kentaurus system between his first infiltration mission and end of the war in 2552.
The Martian Exosolar Command (EXOCOM), unofficially called the Centauri Command after its primary arena of combat during the eponymous conflict, is the most self-contained combatant command in MARSCOM, and is devoted to the enforcement of Martian legislation beyond the confines of Solar Space; it is also well-known as the most unorthodox of MARSCOM’s commands, as the roughly 350 thousand spacers therein are part of an insular, tight-knit community as a result of the conditions under which they are required to operate.
As part of the response to the rebellion in Alpha Centauri, Martinez is deployed as part of an undercover task force on Talvan; while there, he has his eyes opened to the Martian Federation’s shortcomings, seeing things that make him question what he thought was the black and white morality of the conflict throughout the frontier; this is especially evident in how Mars tramples the society developing in the outer solar system as part of a “new colonialism” that only serves to further the astropolitical agenda of Mars-based economic interests; in short, while he is embedded among the citizens of the frontier, he starts to see them as a significant people in their own right, which challenges the dogma of the Martian Federation
The Setting

(Infographic on the major locations on Talvan, Eddie's main haunt during Rebirther)
Talvan, the largest moon of Caliban (official name for Alpha Centauri Ab), was first reached by humans in 2282 as part of the Interstellar Consortium’s Project Wayfarer, which aimed to establish a human presence on worlds outside the solar system by the end of the 23rd century. After a twenty-three-year journey, the more than six thousand passengers of the four Wayfarer vessels that made the crossing from Sol set up a colony in the Rigil Kentaurus (Alpha Centauri A) system, which grew rapidly in the following centuries thanks to an influx of rogues and pioneers aching for new opportunities and, more often than not, seclusion.
By the early 26th century, however, the thriving society in the Centauri cluster had become the center of a much more incendiary series of events, as part of a proxy war that was part of the Kuiper War raging back in Solar Space. This conflict between the Solar Union and the ascendant Martian Federation dragged on for more than twenty years, and took place across the outskirts of Solar civilization.

(Map showing the climate classification of regions on Talvan)
The Centauri branch of this war ignited as a result of Martian attempts to control more of the Centauri cluster, which had been a major point of contention ever since the Crimson Revolution, when MARSCOM military officers led by Colonel Sanyar Galvani stormed the Martian Parliament to demand a reformation after decades of socioeconomic decline. As the new Martian Federation broke with the rest of the ICA, fighting in the Rigil Kentaurus system broke out as agents of Mars and the Ceres-led Solar Union fought each other and a local rebel cell called the Centauri People’s Front, which aimed to evict both from their space.
By 2531, the 350 thousand spacers of the Martian Exosolar Command active in Centauri space have insinuated themselves into the local society, especially the members of the elite Special Reconnaissance Task Force. This unit was devised to infiltrate local populations to gather ground-level intelligence on enemy forces (in this case, Centaurist rebels and spacers of the Solar Defense Corps spacers) and facilitate their being targeted and neutralized by more traditional special operations forces within EXOCOM.

(Infographic comparing three major worlds in the universe of Rebirther)
This is in the same timeline as Spacers Saga?