In 938 BCE the San'Shyuum first encounter the Sangheili on their frontier world of Ulgethon.[1] Like the Stoics, the Sangheili believe that Forerunner relics are to be worshipped, not modified.[2] The San'Shyuum attempted diplomacy with the Sangheili by sending a delegation to explain that they, too, worshiped the Forerunners. Led by an Arbiter, the Sangheili resisted their entreatment and summarily executed the delegation, sparking San'Shyuum-Sangheili War.[3]

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