The Battle of Aereen was between the Galactic Republic and the Confederacy of Independent Systems during the Clone Wars.
Early during the Clone Wars, the Trade Federation established a mining colony on the mineral-rich moon Aereen to support Decimators factories on Krant.
Echuu Shen-Jon looking at the destroyed Trade Federation base on Aereen.
The Trade Federation had built a base on Aereen and had begun to produce an army. Echuu Shen-Jon and Nat Reath arrived with an attack force and began fighting their way through the turrets and Trade Federation forces. Eventually, the Republic forces made their way to the main base and destroyed it, along with the Neimoidian leader Plure Barron.
A Republic base installed on Aereen.
After the base's destruction, General Echuu Shen-Jon installed a base on the moon to prepare for the attack of Krant.