The Seven Hour War occurred on September 29th, 2022. It was a successful revolt against the ESA, conducted by the inhabitants of the recently constructed O'Neill 2 spacestation, leading to the formation of The Highrider Confederation.
In 2022, during the ongoing Fourth Corporate War, the European Space Agency was in the process of completing construction of an orbital space station titled O'Neill 2 (also referred to as Galileo Cylinder and sometimes referred to as O'Neill Gateway), utilizing the highly skilled Highrider workforce originally engaged to build the O'Neill 1. The ESA had recruited workers to the project using catchphrases that included "We'll open the door to the universe." and "The Solar System - a home to all.", drawing ambitious technologists that dreamt of enabling humanity's expansion into space.
Upon leaving Earth, workers for both projects were stripped of their freedom, forced to work excessively long hours under arduous conditions in extremely dangerous environments, given little to no time for rest or recuperation. The ESA, operating similarly to other corporations of the era, employed harsh authoritarian measures to ensure workers would comply with the regime. Peaceful protest of working conditions was met with violent, disproportionate use of force, employed with the intention of breaking the spirit of the workforce.
On the 29th of September 2022, driven by the boiling over of the long conflict between the colonists and their ESA stationmasters, as well as the very real fear of being caught up as collateral damage in the ever intensifying war between corporate rivals Militech and Arasaka, the inhabitants of O'Neill 2 staged an effective, cleverly and quietly organized coup of the entire station, taking complete control. Having observed and understood the resources available to ESA security and potential reinforcement timescales, their plan was simply to overwhelm the station's security forces. They knew they outnumbered security forces 40:1 and that, simply, there weren't enough guns on the station to stop them all.
Once in control, using skills acquired during the construction and operation of the stations, the Highriders deployed the ortillery capabilities of the O'Neill 2, exercising a show of force against the ESA and EEC. Orbital bombardment of a number of key ESA and EEC facilities began, as well as the tactical, defensive destruction of a number of corporate owned orbital weapons.
The entire conflict lasted just 7 hours. The ESA had dedicated much of its available security force to defending planet-side interests from overspill of the ongoing ground war, thus being unable to quickly deploy forces to protect the station. The result of the ESA's hubris was ultimately that control of a number of cataclysmically powerful mass drivers had been lost, then consequently deployed against both themselves and their counterpart, the EEC, to devastating effect. Once bombardment ceased and the stations were deemed to be clear of imminent retaliation, the Highrider colonists of O'Neill 2 declared their independence along with all other Low Earth Orbit colonies, aligned to no particular power and considering themselves neutral to the ongoing ground war.
Given the sheer scale of power now wielded by the newly founded Confederation, the governments of Japan and the United States of America, eager to garner the support of an orbital group no longer under the control or influence of the ESA, were quick to recognize the legitimacy of the new Highrider Confederate government.