Tartarus

Apex Chieftain Tartarus was an influential brute chieftain in the Covenant who unified the disparate Great Tribes and usurped the Sangheili.

Biography
Enlisting into the Ministry of Resolution, Tartarus was selected to join the pack of his uncle, Chieftain Maccabeus, who personally trained and tutored the young Jiralhanae in the art of war. As one of the first converts of the Covenant religion, it was his uncle's hope that Tartarus would one day succeed him and carry on his task of increasing the standing of the brutes.

Tartarus was serving as the chief of security of his uncle's ship, the Rapid Conversion when it received orders to investigate the loss of the Minor Transgression, and the unusual massing of relics detected on what was then the unidentified human colony of Harvest. As the peace talks broke down and the First Battle of Harvest began, he defeated Maccabeus in single-combat and led his pack to victory over humanity.

Over the course of the war, Tartarus continued to rise through the Covenant's ranks, and continued his uncle's work. He used his sound strategic mind and ability to earn the loyalty of his Jiralhanae-dominated units, and under his command they won battles that more prestigious Sangheili legions would consider futile, even suicidal. Eventually, he defeated and took over Apex Chieftain Garus as the Chieftain of the Jiralhanae, and became the representative of his people to the Hierarchs.

It was here that Tartarus discovered he had an ally in the High Prophet of Truth. Distrustful of the Sangheili as they began to question the cause of the war, Tartarus schemed with the Prophet to one day overthrow them. He worked hard to heal the divide between the five Great Tribes and align their loyalty to Doisac, preaching virtues centered around Jiralhanae strength and supremacy, and turning their anger towards the Elites and the Gryunjalla. He blended the traditional tribe structure with that of the Covenant religion, and modernized their militaries into a highly-regimented force that took heavy inspiration from the UNSC. Meanwhile, in secret, he assisted Truth's efforts in placing strategic worlds such as Zhoist under Jiralhanae control.

In 2552, Truth began to set his plans into motion. In the aftermath of the Fall of Reach, Tartarus was tasked with secretly assembling the largest fleet he could, in preparation of an assault on humanity's homeworld of Earth, a victory that would dampen the lauded success the Sangheili had prior. While the Fleet of Igneous Ablution was destroyed by a small team of SPARTAN-IIs, the destruction of Alpha Halo, and the later assassination of the High Prophet of Regret had both achieved the desired effect.