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Following the "Infusion incident," where Kig-Yar shipmasters had poisoned the Unggoy's infusions, the Unggoy on High Charity rebelled against the Covenant. While the Sangheili were better warriors, the Unggoy's sheer numbers and fury were such that they were unable to quell the rebellion. In response to this, the Hierarchs of the High Council appointed the disgraced Heki 'Gibadee as Arbiter to end the rebellion. Unable to counter the Unggoy with tactics, 'Gibadee instead proposed a more ruthless solution: a Covenant fleet was dispatched to the Unggoy homeworld of Balaho, and began glassing large portions of the planet. Recordings of the fleet's attack were broadcast back to the lower districts as a message to the Unggoy to cease rebelling or see Balaho destroyed. Unwilling to see their homeworld destroyed, the rebelling Unggoy surrendered.
Although the Unggoy had failed to improve their political position, the Unggoy had proved that they were formidable fighters when forced into the situation. In light of this, Arbiter 'Gibadee proposed that the Unggoy rebels not only be pardoned, but that the Unggoy be properly integrated into the Covenant military, receiving training and weaponry. Despite concerns from the San'Shyuum, the Sangheili agreed with the Arbiter's proposal, and the Unggoy were integrated into previously Sangheili-only units. 
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