Sojourn was a MUD founded in 1993. During its lifespan, it was regarded as a leading source of innovation and content creation. At its height, it was extremely popular and content-rich. It was based on the Sequent derivative of the DikuMUD codebase.
^Shah, Rawn; Romine, James (1995). Playing MUDs on the Internet. John Wiley & Sons, Inc. p. 93. ISBN0-471-11633-5. "Memorization lives on, however, in Sojourn DikuMud, now the leader in advanced code and new Zone creation."
^ abcTowers, J. Tarin; Badertscher, Ken; Cunningham, Wayne; Buskirk, Laura (1996). Yahoo! Wild Web Rides. IDG Books Worldwide Inc. p. 145. ISBN0-7645-7003-X. "Once upon a time, boys and girls, there was a gargantuan MUD named Sojourn. It had over 400 players at peak times, and some of the most highly modified code in the land. Following faithfully in the wake of TSR's Forgotten Realms (AD&D), the MUD enjoyed an enormous wealth of areas, characters, and ideas from that role-playing game. But gods are vain and so are coders. Having different opinions on the future direction of Sojourn, they took the code and went their separate ways. The world was split into two main offshoots: Duris and Toril."
^Shah, Rawn; Romine, James (1995). Playing MUDs on the Internet. John Wiley & Sons, Inc. p. 35. ISBN0-471-11633-5. "This code is moving into a new version named Copper III, which should be present on the given Mudlist. When this Mud went down in mid-1993, a different Mud spawned from it into what was known to many as Black Knights Realm [...] The creators of this world would move on later to form [...] Sojourn."