The Republic Ambassadorial Corps was a group operating inside the Galactic Republic prior to the start of the Clone Wars, which was fought against the Confederacy of Independent Systems. The Eta-class shuttle, built by Cygnus Spaceworks, was first intended as a VIP vehicle for those in the Republic Ambassadorial Corps.
This Republic Ambassadorial Corps is referenced in Rise of the Separatists. This is a supplemental RPG book for the Star Wars Roleplaying series, released by Fantasy Flight Games in 2019.