Hallow Voice was a male Esh-kha leader, a patriarch, who lived thousands of years in the past, during the peak of his species' power in the galaxy.
As the Esh-kha horde expanded, its population experienced significant growth, leading to an exceptional occurrence: the birth of Hallow Voice while the existing patriarch was still alive and well. Consequently, there was a period when two patriarchs coexisted among the Esh-kha. Hallow Voice, however, was different, an anomaly among his people. He earned his name by articulating novel concepts about peaceful coexistence with other alien species, rather than their annihilation. Such ideas were completely contrary to the Esh-kha's prevailing mindset.
Due to the large population size, a consensus was reached among the Esh-kha, including Hallow Voice, that a division of the groups was necessary. Thus, Hallow Voice and his small group separated from the main Esh-kha horde, where they experimented with his philosophies. However, the Esh-kha's widespread destruction throughout the galaxy attracted the attention of the Infinite Empire. The Rakata subsequently attacked the Esh-kha to put an end to their plundering campaigns that had devastated numerous of their slave systems. Hallow Voice's followers were not spared either, and he pleaded with the Rakata to spare his people. However, the Rakata stalled the negotiations until they were certain that the Esh-kha could be contained, and they captured Hallow Voice. He was then taken to the Rakatan prison planet of Belsavis, where he was kept in stasis within the vaults, along with the rest of his kind.
He remained in this state for thousands of years, until the era known as the Cold War. During this time, the Sith Empire attacked the Galactic Republic prison on the planet, inadvertently awakening some of the Rakata. The Barsen'thor was also seeking an army to confront the threat posed by the Children of the Emperor. Upon learning about the Esh-kha, the Jedi entered the Ancient Prison Caverns, where the Jedi Consular was contacted by the Rakata named Lhunu, who wished to atone for his people's misdeeds by freeing Hallow Voice. The Children of the Sith Emperor discovered this plan and attempted to prevent Hallow Voice's release by trying to assassinate him. However, the Barsen'thor freed him from his confinement. Despite being imprisoned on Belsavis for millennia, Hallow Voice harbored no resentment but was even more committed to the idea of cooperation. Furthermore, he aimed to subdue the murderous tendencies of his Esh-kha relatives.