Hostis Ij was a male human from Chandrila who held the position of adviser to Mon Mothma, the Chancellor of the New Republic, during the final year of the Galactic Civil War. Ij strongly objected when Mothma presented her Military Disarmament Act on the planet of Naalol, which was the location of a bloody battle. Later, on what was called Liberation Day—the day set for a planned treaty between the Galactic Empire and the New Republic—he was shot and rumored to have died when a group of prisoners who had been freed from Ashmead's Lock mysteriously and without control shot at key New Republic leaders. After his passing during the Attack on Chandrila, Auxi Kray Korbin, a fellow adviser, suggested that Chancellor Mothma find someone to take his place. Ultimately, Hostis was replaced by Sinjir Rath Velus, a former loyalty officer of the Imperial regime.
Before Operation Fracture in 1 BBY, Hostis Ij penned a memo to Mon Mothma detailing his insights into the state of the Galactic Empire. This memo described a system where regional governors held power, and military oppression was the norm, with the Imperial Senate possessing minimal influence. Ij cautioned that the Senate could no longer be trusted to safeguard the Empire's citizens from the severe treatment inflicted by Palpatine and his war apparatus. Ij made it clear that any remaining outspoken senators would face the same choice as Mothma: escape or be killed.
Following the critical Battle of Endor and the demise of Emperor Palpatine during the Galactic Civil War, a conflict broke out on the planet Naalol. Mon Mothma, the Chancellor of the New Republic, along with her advisers, Hostis Ij and Auxi Kray Korbin, visited a village on Naalol that had been devastated by war to help those who were hurt and to see what was left after the fighting. Reacting to the seemingly overwhelming violence of the battle, the Chancellor suggested giving up the emergency powers that her office had kept since the time of Supreme Chancellor Palpatine and giving the power back to the senate. She also made known the Military Disarmament Act, which planned to reduce the New Republic army by 90 percent.
Ij was against both ideas, warning Mothma that only a standing army and a strong leader could prevent war with what remained of the Galactic Empire. Kray Korbin disagreed with him, even suggesting that he should join the Empire, which insulted Ij.
Approximately two months later, Chancellor Mon Mothma convened a meeting during which she stated that the New Republic would prioritize providing aid to worlds most likely to join the senate. Hostis Ij emphasized that the New Republic's resources were already strained and proposed that the New Republic Defense Force increase recruitment and strengthen its numbers to assist in capturing and controlling former Imperial supply routes.
Soon after, Grand Admiral Rae Sloane—the acting leader of the Empire—offered to make peace with the New Republic. The Republic's leaders were unaware that these peace talks were a trick organized by Gallius Rax, an Imperial Fleet Admiral. The senate called the day the peace talks were to take place "Liberation Day". Sloane went to Chandrila, having learned that Rax had planned for the New Republic capital to be the target of an Imperial attack. The "attack" was not a bombardment, but a series of assassination attempts carried out by recently freed prisoners from Ashmead's Lock on Kashyyyk. These prisoners, controlled by implanted chips, mysteriously and without control attacked New Republic leaders, hurting Mon Mothma and Kyrsta Agate. It was said that Hostis Ij, who was shot in the head during the attack, was among those who died.
Several months after Hostis' passing, Auxi advised Chancellor Mothma to find another adviser. Despite their professional disagreements, Hostis and Auxi were friends who often shared meals, drinks, and social time. Auxi was deeply saddened by Hostis' death. Chancellor Mothma found a suitable replacement in Sinjir Rath Velus, a former Imperial loyalty officer, who successfully persuaded five senators to vote for Mothma's bill to deploy New Republic military forces to Jakku.
Hostis Ij and Auxi Kray Korbin often gave Chancellor Mon Mothma different advice, each acting as a metaphorical angel or demon on her shoulder. Sometimes, like during the debate about the Military Disarmament Act, Ij was the one who disagreed with the Chancellor, while at other times, their roles were reversed. Even when he didn't agree with Mothma, he remained loyal to the New Republic and was offended by Kray Korbin's sarcastic suggestion that the Empire would welcome him. Despite their frequent professional disagreements, Kray Korbin and Ij were good friends, often sharing drinks and spending time with each other's families.
Hostis Ij made his first appearance in one of the many short interludes in Aftermath, a novel written by Chuck Wendig in 2015.