The Succession

0 Years Before Succession, New Standard Calendar
Earth has had widescale wars ever since the mid 20th century, many of which involved near-Earth platforms, but such conflict only spilled over to involve solar and extrasolar resources for the first time during the 7th World War.
Before the Contact War true militarized assets in space were limited, and mostly concentrated in Earth orbit anyway. Prior to the creation of the High-Entropy Compression Swap travel back and forth between Sol and its colonies could easily take a decade or more, meaning that attempting to rope in extrasolar assets would have been a fools errand anyway if they had existed.
The 7th world war was the first major military conflict to erupt on Earth after the contact war and the development of the warships used to fight it. Between those weapons, and access to faster than light travel, space became an active theater in Earth's conflicts directly for the first time.
The warships in Sol were drawn into the fighting immediately, ships belonging to one nation firing upon its enemies. Given that these ships were designed to deliver nuclear payloads, the damage was extensive. Over the course of the war several space stations were destroyed, as well as two cities on Mars and the Mars Web, leading to a near total collapse of terraforming efforts on Mars that still has not recovered to this day. 4 orbital strikes from deep space battleships were also performed on Earthside cities and military bases, to say nothing of missile strikes and conventional weapons that took place on Earth itself.
As the fighting escalated and the stakes were raised, those nations with extrasolar holdings demanded reinforcements from the colonies, or attacks on other colonies to prevent those reinforcements from arriving. Aware of the fighting in Sol, the colonies were extremely apprehensive about joining the conflict as combatants. Previous wars on Earth had been no concern of theirs, and while each colony technically owed allegiance to forces on Earth none of them felt strongly invested in what was ultimately a small territorial dispute by the standards of the colonies, which were ultimately more concerned with entire planets.
Rhineland, Capital and Proceka came together in secret meetings and agreed that the time was right to cut ties with Earth. However, they also recognized that the industry resources of Earth made them too dangerous to leave alone. Earth would inevitably seek to enforce its claim to the colonies with military power, and that was a war that colonies may very well lose.
Instead, the colonies chose to take action and remove Earth's ability to threaten them preemptively. A combined fleet enter the Sol and quickly overran the exhausted space based defenses already present there. With the few platforms capable of opposing them taken care of, the fleet was able to eliminate remaining Earth-loyal military forces from extreme range. Within just two days the colonial fleet had achieved orbital supremacy over both Earth and Mars, and effective control over the entire system.
Systematically dismantling the satellite network above Earth, as well as destroying the two remaining space elevators, the colonies began the Terran Blockade. They decreed that Earth no longer held claim to any territory or resource beyond its own atmosphere, and any attempt by any Earth nation to reach space would be prevented by force. With its existing orbital infrastructure destroyed, and fighting against its own gravity well, Earth was in a naturally disadvantaged position to break the blockade. A situation exacerbated by the fact that they were still in the grips of a world war amongst themselves, as well as a swiftly impending economic collapse resulting from the larger powers ( the ones most invested in solar and extrasolar resources) being cut off from crucial resources.


The Terran Blockade spelled trouble for more than just Earth nations. Many colonies had no say in the removal of Earth's authority, or indeed any warning. The Samran colony in Tau Ceti condemned the actions of the colonial fleet, and many stations and colonization projects suddenly found themselves cut off from patron nations and supply lines they depended on. The Colonial Oversight Authority, for much of its existence a paper tiger of an institution, overnight became the only thing keeping the smaller colonies from falling apart. But despite its best efforts some stations ceased to exist entirely, and the Twin Systems project of Lalende and Wolf suffered a cascade of calamities, only barely surviving with incredible losses.
Over time the dissenting colonies were brought to heel, typically due to necessity rather than under threat of force. Now needing to plan a future without Earth, the beginings of the United Colonies of Humankind began to form. From the start, it was decided that for any hope of the UCH to succeed, Earth would have to remain cut off from space until such time that it no longer presented a threat, either militarily or culturally. Alongside the political and economic reorganization came the groundwork for a culture war planned out for decades into the future, de-emphasizing the importance of Earth, its nations, and its history in favor of the the history of the colonies and their glorious future.
In the the history books this time period is known as The Succession, the time in which the colonies succeeded Earth as the primary focus of mankind.