From Halopedia, the Halo wiki
Jad Sappar was the Forerunner name for a location in the Milky Way galaxy. One of the concluding battles of the Forerunner-Flood war was fought beyond Jad Sappar, between the last combined Forerunner fleet and the Flood, the latter's parasitized fleet supported and protected by thousands of Precursor star roads. After the battle, the remaining Forerunners took refuge on the greater Ark, which would also soon fall under attack.
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