In 29 ABY, a secession occurred when a significant number of star systems aligned with the Centrist faction formally broke away from the New Republic. These systems then established the First Order, which had previously existed as an unrecognized military junta operating from the Unknown Regions. This act of secession marked the beginning of a widespread resurgence of Imperial-style militarism and fascism throughout the known galaxy.
The First Order originated from remnants of the defeated Galactic Empire who had fled to the Unknown Regions after the Galactic Civil War concluded with the end of hostilities. In the years prior to their secession, the First Order allegedly exerted covert influence and control over the New Republic through clandestine agents and sympathizers.
Upon its formal establishment, the First Order and the New Republic immediately entered a Cold War that ultimately escalated into a full-blown galactic war in 34 ABY. By 35 ABY, the First Order had successfully conquered a substantial portion of the galaxy.
By 28 ABY, most of the remaining remnants of the former Galactic Empire located within the Core, Colonies, and Inner Rim regions of the galaxy had integrated into the New Republic. These former Imperials reorganized themselves into a political faction known as the Centrists. This integration created friction within the New Republic Senate, as Centrist senators advocated for a more centralized New Republic government and a stronger military, similar to the Galactic Empire. Conversely, the Populist faction, composed of senators from the Republic's founding systems, favored decentralization and demilitarization, mirroring the structure of the Galactic Republic prior to the Clone Wars. Leading up to these events, the Amaxine warrior crisis unfolded, revealing that prominent New Republic political figure and Rebel Alliance hero Leia Organa was the daughter of the widely reviled Darth Vader. Influential Centrist Senator Lady Carise Sindian of Arkanis, secretly working for the First Order, orchestrated the assassination of Populist leader Tai-Lin Garr through her ally and fellow First Order supporter Arliz Hadrassian. This crisis resulted in the postponement of the creation of a "First Senator" position, a role designed to possess greater authority than the Supreme Chancellor and proposed by the Centrists to resolve the political deadlock that had plagued the senate for years.
Following the controversy surrounding Senator Organa, she resigned from her position in the New Republic Senate and established the Resistance to combat the rising tide of Imperial-style militarism embodied by the emerging First Order. Carise Sindian had planned to introduce a motion in the Senate that would allow Centrist worlds to secede from the New Republic. Although Organa was able to ruin Sindian's political standing, a majority of Centrist systems followed through with her plan and formally withdrew from the New Republic. Among the planets that seceded were Orinda, Kuat, and Arkanis.
Most senators welcomed this departure, and the Senate permitted their withdrawal, a stark contrast to the Separatist Crisis that triggered the Clone Wars. The former Centrists then reorganized to form the First Order, officially establishing the regime and initiating the Cold War between the First Order and the New Republic. The First Order, built upon the remnants of the Empire's war machine, signaled a resurgence of fascism and militarism, with Snoke, a dark side adept who rose to become the Supreme Leader of the faction, taking control of both politics and the military.
Subsequently, the First Order consolidated its control over the territories within its sphere of influence and launched invasions into several neighboring systems. These included the Otomok system (which was subjected to a blockade), Tehar, and planets like Castilon and Jakku. As tensions escalated during the Cold War, an increasing number of planets found themselves under the influence of the First Order. The majority of First Order incursions occurred in the Trans-Hydian Borderlands to the north.
Despite the First Order's blatant invasions and occupations of worlds in the Mid and Outer Rim, the New Republic refrained from taking direct action against them, limiting its response to official condemnations. This inaction prompted the Resistance to undertake military operations against the regime. Eventually, the First Order would destroy the New Republic Capital, leading to both full-scale war and the First Order's temporary, yet significant, success in its ambition for galactic domination.