It's one of ten background songs in the game.
Curious when the song heard in-game, it stops at 2:21 and skips to the next track. However, if the player is currently in the Pause menu, it will be heard in its entirety. It is unknown if this is caused by a bug, or if it is a deliberate easter egg.
Dune II: The Building of a Dynasty (AMI)
Dune II: The Building of a Dynasty (ARCH)
Dune II: The Building of a Dynasty (DOS)
Internal file names are DUNE5.XMI, DUNE5.C55, DUNE5.TAN, and DUNE5.PCS.
Internal file name is DUNE5.ADL.