Wolfenstein
The "Wolfenstein" series of video games started with the 1981 stealth-adventure video game "Castle Wolfenstein". It was developed by American programmer Silas Warner, a pioneer in the early eras of video gaming, especially the stealth genre. It was published by his (then) company M.U.S.E. Inc. (Muse Software). The player controls an unnamed American prisoner of war as he steals war files containing information about secret German war plans while avoiding or sometimes killing guards, and tries to escape the fortified Nazi stronghold Castle Wolfenstein, set during World War II. The game is often credited as one of the first video games of the stealth genre, since it focuses more on avoiding or disarming enemies, and killing them is considered a last resort.
Return to Castle Wolfenstein
In the United States, "Return to Castle Wolfenstein" sold 350,000 copies and earned $17 million by August 2006. It was the country's 48th best-selling computer game between January 2000 and August 2006. Combined sales of all "Wolfenstein" computer games released between January 2000 and August 2006 had reached 660,000 units in the United States by the latter date. "Return to Castle Wolfenstein" received a "Silver" sales award from the Entertainment and Leisure Software Publishers Association (ELSPA), indicating sales of at least 100,000 copies in the United Kingdom. By January 2002, Activision reported that shipments of "Return to Castle Wolfenstein" to retailers had surpassed one million units.