I'm playing a game as humans. My explorer ships discovered the Sol system with a continental planet that is already colonized by independent humans. I've tried the tutorials and read the manual, but can't find the specifics of how I can colonize it. Any help would be appreciated.
If a planet has a independet colony a check is made during colonisation, either they accept becoming part of your empire and their population is added to your new coloniy or they resist and fight your colonists, most likly killing them.
The description of the independet colony should show a additonal infobar if you click at the coloyship and hover over the planet or loock at the expansionplaner..something like....they will most likly join our empire/colonisation is unlikly because of...
Take into mind...the chance of colonisation is mostly based on the behavior of the race(s) living at the colony and the race of the colonyship, the relationship of your empire towards that race is less important.
Soo...if a colonisation is unlikly, just try a different race from your empire.
So..long story cut short, just colonise them like all others, just check the chance of resistance.
Edit: You can also conquer independet colonies, most the time is much easier&faster to send a tropptransport with some inf. send building a colonyship, but conquering independet colonies will lower your reputation a bit and the new colony will get some small drawbacks.