Be it forest, mountain, plains, or riverlands, there exists a lot of territory outside of the control of the Alesian Empire. These frontier lands are oftentimes more wild, and always more dangerous, lacking the resources the Empire has to keep it’s citizens safe. Oftentimes, it comes down to the individual to protect himself.
Leadership outside of the Empire can be a nebulous thing. Without the Nexus to look to, it really comes down to who can take power, who can hold onto that power, and who can convince everyone else that they have the right to that power. It also comes down to how well they are able to enforce that rule. Some places are ruled by mayors or governors or councils of elders. Others are under the rule of warlords or self-made kings and princes. It really depends on the area and the population, and is a constantly shifting thing.