Jeff Strain, the driving force behind Guild Wars and Co-Founder of ArenaNet, has left NCsoft West. He had, since NCsoft’s North American reorganization last year, served as the President of Product Development for NCsoft West and was considered by many to be the primary creative mind at the company.

Also departing is their President of Publishing David Reid.

NCsoft West Public Relations Director Ryan James responded to MMORPG.com’s inquiries with two statements. First, regarding Strain:

“With a successful history creating MMORPG games, NCsoft has made an indelible mark on the games industry. Last year, the South Korea-based NCsoft created a division to follow a vision of bringing AAA MMOs to the West called NCsoft West. This organization was formed as part of NCsoft’s ongoing vision to be the premier global MMO publisher in the world. With that vision, change in a growth industry is inevitable. NCsoft West announces the departure of Jeff Strain, President of Product Development, who has chosen to leave NCsoft under amicable terms and NCsoft wishes him the best in his new endeavor. This does not change our plans or negatively impact our upcoming launch of Aion, and NCsoft remains very excited about the game’s launch on September 22nd in the U.S. and September 25th in Europe. These changes do not influence any other teams, development schedules or other launches.”

Then, regarding Reid’s departure:

“In an unrelated and separate event, David Reid is no longer with the company. David joined NCsoft in early 2008 as vice president of marketing and helped in the formation of NCsoft West and the relocation of our headquarters to Seattle. David brought passion and talent to our organization, and he will be missed.”

Prior to Co-Founding ArenaNet and launching Guild Wars, Strain was the Lead Programmer for Blizzard’s World of Warcraft. At the Irvine developer, he also contributed to Diablo, Starcraft and Warcraft III.

Reid had previously lead marketing efforts for Microsoft’s launch of the Xbox 360 and GameTap, an online game portal.

The moves come with just over a month left until the North American launch of Aion, which could be very important for the company’s Western operations after a string of high profile setbacks that included Auto Assault, Tabula Rasa, the departure of the Garriott brothers, and shuttering the bulk of their former North American headquarters in Austin, TX. Aion is due to launch on September 22nd, 2009. It also remains to be seen what, if any, impact this will have on the eagerly anticipated Guild Wars 2.