Arin is a human core planet serving as a great center of political influence, economic development, and military strength that is of critical and strategic importance for humanity. As a core planet, Arin provided significant financial, material, and other resources to AE and the Knight Order while being exempted from mandatory conscription although its self-defense group, the AUA, still voluntarily deploys expeditions to the vulnerable frontiers of the Absolute Defense Line.
Arin is different from other core planets in that it is de facto seen as the capital of humanity since it hosted the Central Order Supreme Headquarters of the Knights. Given its power and wealth, it is presumed that Arin's scope is very broad and far-reaching. Besides Planet Arin itself, the term Arin as a polity encompasses several nearby colonies orbiting the planet such as the 7th Colony of Arin and other celestial bodies within the same system.
Both the Main and Another episodes of Knight Run are either set in Arin or are highly influenced by the events that occurred in it. As such, Arin is a central setting to the whole series. Main Episode-0 Pray covers the Pray War which saw the fall of Arin and the struggle to retake it from the Beasts.
First Battle of ArinEdit
War of PrayerEdit
- Main article: War of Prayer
Arin maintains a highly disciplined, experienced, and modern self-defense force known as the AUA. It is an extremely distinguished and reputable military force due to having a very powerful potency that could even rival AE. It is implied therefore that AUA is the largest armed force there is, second only to the main unified force of the AE alliance.
The AUA is very active in participating in the Human-Beast conflict. It routinely sends expedition forces to the frontiers to provide auxiliary reinforcements to conflict zones and other battles against Beasts.
The Knights settled in Arin when Mother Knight, with close assistance from the Zail Family and Leonhard Family, restructured the humanitarian aid support/anti-Beast R&D organization "PF" to the independent paramilitary group known as "Knight Order". Eventually, the Knight Order decided to expand their structure upon gaining official recognition and support from AE. The Northern, Eastern, Western, and Southern Orders were established as branches of the main Central Order that remained in Arin as the overall supreme command and headquarters of the Knights.
The Knight Order academy, known as Knights Training Organization, was staffed and handled by Central Order. This made Arin the main recruitment and evaluation site for prospective Knight trainees.
Fleeing the disastrous collapse of their empire during the Great War, the Zail Family made Arin their second home and new base of power after co-founding the Knight Order alongside Mother Knight and the Leonhard Family. It is implied that the Zail Family has substantial influence on the Arin Government and Knight Order. The Zails also have direct ownership and control over huge swaths of Arin's territory while maintaining their own personal army and navy.