The Factions are the groups that have both an interest and the means to colonize other worlds. Each faction gains bonuses and penalties, with different Victory conditions, based upon their principles and approach to hominization.
The UNSA focuses on cooperation in the form of democracy and an educated populace at the cost of slower monetary gain. Meanwhile The Horizon Corporation sacrifices those ideals in the pursuit of financial gain, and the Far-Future Institute dedicate themselves to cutting-edge development and scientific discovery.
Cultural starting positions can for the most part be changed during the game by spending culture points, so it's better to choose a faction based on what you want your end goal to be; paradise habitability, giant population, ridiculous amounts of revenue, earning 20 culture points without changing a planet's starting stats, or researching all technologies.
Depending on the faction you choose, there are limits to what your world's culture can be. For example, if you choose Horizon Corporation, your Knowledge Value (research speed boost) can never be higher than +0%. In exchange, your Wealth Value (financial growth) stat can never be lower than +0%.
One of the earliest groups advocating for off-world terraforming, the Daughters of Gaia were founded by the charismatic Eleanor Lee and have since become a powerful force in Earth politics. Under your leadership, the dreams of the Daughters will finally become reality: the transformation of an alien world into a new garden paradise.
Satellite: Reduced cost for Soletta.
Culture Limit: Cannot choose Industrial Economics.
Not everyone believes that we have the right to transform entire planets to suit our needs. Chief among the leaders of the conservation movement are the Sons of Hephaestus, a Planetary Purity splinter group dedicated to colonization methods that do not "contaminate" the host planet. Pioneers in advanced habitations, the Sons have members in nearly every known off-world colony.
Goal: Achieve independence, and retain starting habitability (keep all stats within 5% of their starting positions; if your stats change a lot, there is no 'game over', you can just change them back and it's fine).
Satellite: Reduced cost for Sky Farm.
Culture Limit: Cannot choose Transformation Eco-Policy.
After the Sundering, the surviving nations of the world agreed to pool their resources into a combined, truly international space exploration effort. After a few high-profile successes and the return of a relatively stable economy, the UNSA is poised to take its greatest step yet: the international colonization of an entirely new world, in the name of a united Humanity.
Satellite: Reduced cost for Lagrange Academy.
Culture Limit: Cannot choose Plutocratic Government.
The Horizon Corporation was one of the first powerhouses of spaceflight, and has since come to dominate the interplanetary market. Never content to stand still, though, Horizon is about to unveil their most ambitious plan yet: the single-handed transformation of an entire planet into a new, corporate civilization.
Satellite: Reduced cost for Orbital Surveyor.
Culture Limit: Cannot choose Knowledge Values.
Founded by scientists, futurists, inventors and philanthropists, the Far-Future Institute is an international society dedicated to reshaping humanity's future through cutting-edge science. The FFI envisions a world beyond petty corporations, religions, and governments, a world where policy is guided by science, where expertise is king, and where even the sky isn't the limit for long.
Goal: Achieve independence, and research all technologies.
Satellite: Reduced cost for Space Elevator.
Culture Limit: Cannot choose Wealth Values.