Amarin, characterized by its thick, expansive forests, existed as a planet within the Amarin system. This system was situated in the Allied Tion sector, and Amarin stood out as one of the most productive agriworlds found in the Tion Cluster.
Amarin's discovery dates back to approximately 25,127 BBY. Initially, it was a part of the Kingdom of Cron until Xim the Despot's empire absorbed it. Under Xim's rule, Amarin was repurposed as a hunting ground. Following the empire's downfall in 25,096 BBY, the Kingdom of Cron regained control and maintained its independence. Several millennia passed before Darth Revan's Sith empire encompassed the planet, lasting until its collapse in 3960 BBY. Choosing to remain separate from the Republic, Amarin aligned itself with the Brotherhood of Darkness during the New Sith Wars. However, the planet was seized from the Sith after their defeat, a few years prior to the Ruusan Reformation.
After several centuries as a member of the Republic, Amarin, along with the rest of its sector, joined the Confederacy of Independent Systems during the period of the Clone Wars. Although the sector witnessed several battles, the Galactic Empire took control of the planet after the war's conclusion. The Emperor, viewing the region as a potential threat, divided it into three distinct sectors, with Amarin being incorporated into the Allied Tion sector. During the Galactic Civil War, the Warlord patrolled the system. It then joined Grand Admiral Thrawn's confederacy, only to be placed under the authority of Sector Moff Gronn after Thrawn's demise.
The Allied Tion, including Amarin, established an independent government separate from the New Republic, successfully avoiding involvement in the Yuuzhan Vong War. By 137 ABY, Amarin was integrated into Darth Krayt's Galactic Empire.