The Eta Omega chapter of Theta Chi was founded by Mark Geenen in 1982. Geenen had been initiated into the San Jose chapter of the fraternity before transferring schools to CSU Chico. In January of 1981, Geenen had assembled ten men to start the new chapter at Chico State. By the next year the fraternity had grown to 50 members making them one of the fastest growing colonies in Theta Chi history. The new colony was installed in 1982 as an official Theta Chi chapter.
Since 1982 we have initiated over 700 members, more than any other Theta Chi chapter in the same time period. We celebrated our 25th anniversary in Chico in 2007, with over 300 attendees coming from as far away as England.