Aleria was colonized in 2341, at the end of a millennia-long period of low solar activity that plagued the Odin system. Upon its conception, Aleria became an exemplary and urbanized Outer colony, known for its rich mineral resources and inspiring economy. However, not long after colonists had been settled on the planet, the UEG's efforts to terraform the system led the planet to become climatically unstable and the temperatures soon rose.
As agriculturists became concerned for the change, the UEG continued to perform several process of terraforming, and Aleria's mining industry rapidly expanded, prompting the establishment of Mols'Desias, a mining union that took control of the entire working force of the planet. Founded under noble goals, it eventually became corrupt, exchanging raw materials they produced to the UEG in trade of goods such as spaceships, electronics and food. The climate change continued to increase, severely decreasing the rains on the planet and leading to a major political unrest that sparked fear among the Alerians. Despite the local government's best efforts to keep the population under control, conditions became worse between the government and the Alerians themselves.
In 2453, a major drought occurred on the planet, which lasted a century, leading the planet into chaos, completely shattering the economy, and reducing its colonists to outlaws, who resorted to raids and petty crimes against others in order to gain resources. During the First Contact War, the remainders of the government attempted to secure support from the UNSC against a potential Covenant, but to no avail, leading many Alerians to rebel against local police forces that still attempted to halt the progress of the sand nomads. Many followed him, believing the UEG to be the source of all of Aleria's problems. As the war neared its middle point, the UEG voted to hold down trade with the planet, which was unanimously agreed in the UEG Senate. After the end of the war, the planet remained outside the control of the UEG and the UNSC.
By 2555, half of the planet's population had dwindled, and the younger Alerians, tired of the oppression and miserable conditions they suffered, started to rise against the criminal forces. Some of Mols'Desias remnants started to resort to crime after cutting all ties with the nomads, such as the pilots of the Bactrian-class freighters, notably smugglers Arris Le and Haisal Wari.
- Humans (introduced)
- Aleria is named after the French commune of the same name.