UNSC Agincourt was a UNSC vessel in operation in the early 2550s. In October 2552, it was sent to planet Onyx to offload supplies at Camp Currahee for the incoming candidates for the new SPARTAN-III Delta Company. As they were leaving, the Camp Commander, Lieutenant Commander Ambrose asked for observational assistance from the craft after hearing strange sounds coming from Zone 67. Agincourt was discovered and was destroyed by two hundred Onyx Sentinels that had been activated within Onyx.
- The vessel is likely named for the Battle of Agincourt, a battle between the English and French during the Hundred Years' War.
- Halo: Ghosts of Onyx (First appearance)