From Halopedia, the Halo wiki
During the Human-Covenant War, Gusay was a crewmember and the personal assistant of Shipmaster Jul 'Mdama. After the war, there was a shortage of warships and he was reduced to be Jul's driver at his ancestral estate of Bekan keep in the state of Mdama. In January 2553, Gusay drove Jul in a Revenant to a meeting where the Arbiter spoke with the state's kaidon, Levu 'Mdama, and the rest of Mdama's elders. Jul later kept Gusay uninformed of his plan to join the Servants of the Abiding Truth and overthrow Thel 'Vadam in the hopes that if he failed, Gusay would escape any kind of retribution.
Gusay appeared to have a respect or interest in humans, and sometimes made references to very human phrases such as "full house". He believed that the Sangheili could learn from humanity in the aftermath of the Human-Covenant War in order to rebuild their society, reclaim their independence, and adapt to a changing galaxy. However, his superior, Jul 'Mdama, would hear none of this, vehemently stating that the Sangheili were nothing like the humans and forbade Gusay from saying otherwise.
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