Here is a short historical background of my Hard Space setting. I posted a history two years ago, but this one is a revised, expanded, and edited one to serve my new (current) iteration of the setting.
World War III and Solar System Exploration: 2038-2063 (TL8)
World War III came about in 2038. Luckily enough, it did not materialize into the all-out nuclear Armageddon feared by many. Instead, the war dragged on for almost a decade until all belligerents were bled dry and exhausted by the long war years. In 2047, the war was finally over. The world was in ruins from prolonged conventional warfare and the few nuclear, chemical and biological weapons that did see use in the war.
All sides claimed victory. In reality, there were no victors - just bankrupt and impoverished nations incapable of conducting any further large-scale military operations. Politically, most governments emerged from the war at a very weakened state. They had very little support from the war-weary population. They were mostly powerless to do anything meaningful to reconstruct the ruins of their nations. Into this vacuum stepped the private sector, thrilled with the possibility of profit from reconstruction. Earth's collapsing nation-states no longer had the political power necessary to force taxes or regulations on the larger corporations. Thus these companies grew rapidly in size and power.
Bit by bit, the corporations rebuilt parts of Earth. Not all of it; not even most of it. The corporate arcologies and gated cities provided their residents with the amenities of modern life, unlike the universal poverty of the urban blight surrounding them. Rising in profits, the private sector turned its eye to research and development, as well as the industrialization of the solar system. In the late 2050's, these efforts bore fruit and resulted in a rapid succession of innovations, from suspended animation to controlled nuclear fusion.
The greatest discovery in the history of space flight came in 2061 when a dig of the Cydonia region of Mars yielded weird alien artifacts. This came after long years of rumors and strange accidents caused to spacecraft and ground vehicles in the vicinity of this region. While the Face of Mars turned out to be nothing but an oddly-shaped hill, the region itself appeared to be visited by extraterrestrial travellers, dubbed the "Visitors" or the "Antediluvians". They left behind cyclopian ruins filled with unexplainable and deadly anomalies warping time and space, as well as a plethora of artifacts, the function of which was never fully discerned so far.
First Colonial Generation: 2063-2082 (TL9)
In 2063, research into Antediluvian artifacts recovered from Mars led to the greatest invention of all times - the faster-than-light Jump Drive. It was demonstrated by a historic month-long round-trip to Alpha Centauri by Zhang-Markov Industries's starship Zhen He. Very rapidly - some would say too rapidly - Iron Star Enterprises followed suit and launches their own exploratory starship, John Glenn, on an expedition to Barnard's Star. Thus began the first generation of space colonization.
Space is dangerous, and interstellar space more so. The first interstellar travellers found this the hard way, with high mortality rates among the early explorers who ran into deadly jump drive malfunctions, vicious alien wildlife - and soon enough, inter-corporate rivalry resulting in bloodshed. But mankind continued its march to the stars, despite the small size of interstellar ships allowed by the early jump drives. Colonies soon sprang out on planets orbiting Alpha and Proxima Centauri, Barnard's Star, and Ross 154, as well as small research outposts on rockballs in orbit around Luhman 16 and SCR 1845 6357.
With the vast profits promised by extrasolar assets, corporate competition grew to enormous proportions. In the absence of any effective government beyond Earth orbit, this encouraged cutthroat methods and led to bloodshed. Warfare began with privateering and small, but overt, mercenary actions. In 2070, it grew up to a full-scale war between UEM's Olympus colony on Proxima Centauri c and the Zhang-Markov Arcadia colony on Alpha Centauri 2f. The war raged for a bloody year. In 2071, mercenaries operating for UEM accidentally (or so the official story goes) caused a meltdown of the fission reactor powering the Arcadia 2A sub-colony. The destruction and death toll - as well as the bad press they brought - brought an immediate cease fire. This made the corporations pause and think - such warfare already began rising beyond acceptable costs, and threatened to destabilize the political situation on Earth itself.
The result was the Interstellar Agreements on Colonial Commerce (IACC), signed in 2072 by the Big Four corporations and the three Trading Blocks. IACC set basic ground rules for extrasolar colonization and commerce, banned overt piracy and claim-jumping, and established the Colonial Commerce Commission (C3). The latter began as an inter-corporation arbitration body but grew to a framework of extrasolar corporate governance. It is not a government, as it does not truly govern individual citizens and holds no armed forces of its own. Rather, C3 is a system operating to serve the common interests of the Big Four and the three Trading Blocks - open commerce, avoidance of overt large-scale warfare, and preservation of the corporate order of things. C3's executive body, the Presidium, holds seven representatives - one from each Big Four megacorporation and one from each Trading Block, giving the corporations, as a group, a majority.
Second Colonial Generation: 2082-2106 (Mature TL9)
In 2082, a transit station was built on a strange rock orbiting the dim brown dwarf HSC0801 (now Sheol), linking Sol to the Solar Main in a Jump-1 chain. This allowed larger ships to travel from Sol to the colonies. Together with the development of more robust orbital shipyards and thus a larger number of starships, the second wave of interstellar colonization in the early 2080's, colonizing seven new worlds, of them only two, orbiting 70 Ophiuchi (Tehom) and Gliese 667 (Agartha), turned out to be highly promising garden worlds, with the rest being more amenable to rare and exotic element mining.
This era saw a rise in local warfare and "police actions" on Earth itself. The Trading Blocks moved to consolidate their hold over Earth's devastated and lawless Wilds, and tighten their grip over the urban Blight surrounding the arcologies. They achieved the latter to a reasonable degree, defeating many of the urban gangs plaguing the old cities. However, taming the Wilds was a failure. Equipped with the best corporate-made equipment their limited budgets can buy, the Trading Blocks tried to force their rule over wasteland areas such as the Rockies, the Levant, and Siberia. They attempted to bring "rogue states" such as Iranistan or the Free Republic of Texas into their fold. This failed miserably. The Wilders - as corporate media often referred to such people - had no intention to be governed by the Trading Blocks. They had better knowledge of their terrain. They had much better morale than the underpaid governmental armies. By the dawn of the 22nd century, the Trading Blocks all but abandoned their dream of reconquering the entirety of Earth.
However, this warfare, as well as the horrible conditions in the Blight and the Wilds, drove interstellar expansion. People were, and still are, willing to risk the deathly perils of cryosleep to reach an extrasolar colony. Even though life is harsh on the colonies and death hides behind every corner, this is still far better than living in the blasted wastelands or shelled-out cities of Earth.
Third Colonial Generation: 2106-Present (TL10)
In 2106, research into the alien artifacts and anomalies - while yet far from bringing about an understanding of the Antediluvians themselves - gave scientists valuable insights into meta-dimensional physics and exotic matter. This brought about a new generation of jump engines, allowing both larger starships and longer travel ranges. This opened up new frontiers to Humanity. New expansion began in full swing, doubling the number of extrasolar colonies within a few years.
Today, in 2120, human space boasts 43 primary interstellar colonies. Most are very small in size, especially the remote ones, though Arcadia (Proxima Centauri III) does serve as a home to almost a eleven million people. The frontier is wide open, and starships are "cheap" enough for smaller corporations and all sorts of social and religious movements to afford. Criminals, of course, can afford them as well, and piracy is a blight on the high frontier... This is a time for daring people to go out of the Sol system and seek their fortune among the stars. Many, however, will find there not their fortune - but their untimely death.