May 05, 1980:
- Ken Williams and Roberta Williams finally release their first computer game - an adventure game called "Mystery House". The game was available in only 4 stores in the L.A county. Ken & Roberta transferred the software personally. The game was released under "On-Line systems", Sierra in its early life.
- Changed name from On-Line Systems to "Sierra On-Line", and moved to Oakhurst, California, in the Sierra foothills.
- Sierra acquired Dynamix.
- Sierra acquired Bright Star Technoligies.
- After acquiring the North American distribution rights for Coktel education software products, Sierra acquires Coktel Vision in 1993.
- Sierra purchases the rights to Print Artist, a program that enables users to quickly and easily create and print their own professional-quality documents.
Jul 24, 1996:
- Sierra is acquired by CUC International.
- Sierra acquired Berkeley Systems, the maker of the best-selling "You Don't Know Jack series. Books That Work was also acquired by Sierra in 1997.
Feb 03, 1997:
- CUC Software Inc. is created by CUC International and includes Sierra On-Line, Knowledge Adventure, Davidson & Associates, Blizzard Entertainment, and Gryphon Software
Jan 28, 1998:
- Sierra Sports brand created.
- Sierra and its affiliates were acquired by Havas Interactive.
May 11, 2000:
- Sierra / Valve announced Half-Life MOD program, where Sierra and Valve will pick the best of the MODs, fund them to be polished to commercial quality, publish them, and make the MOD maker to get both fame and some fortune.
Dec 01, 2000:
- Sierra announced that Ground Control Expansion pack:Dark Conspiracy is available free (you pay shipping) via mail-in offer.
Feb 19, 2002:
- Sierra On-Line changes its name to Sierra Entertainment, Inc.
- Company finally closed down by its parent company Vivendi Universal Games after all other studios and offices had been closed over the course of the year.
- Vivendi Universal Games re-opens Sierra Entertainment with new management.
- Sierra is disbanded, as a result of the merger between Vivendi Games and Activision. All of their TBA titles were either cancelled, sold to other publishers, or published under Activision brand. Most of Sierra's subsidiaries were also sold, or closed, with the exception of High Moon Studios and Radical Entertainment.
Aug 07, 2014:
- Sierra's website is re-activated stating more to be revealed.