The Trex Fraternity of California was founded in 1918 in Fresno, California by eight young men of Armenian descent. The name was chosen to signify the Roman numeral "30," which was the number of members they hoped to eventually attract to the fraternity. In the ensuing years, the organization has grown to number more than 725 members in 12 regional chapters and three local “Junior” chapters (for young men between the ages of 16 and 21) throughout California and Nevada — including the newly-chartered San Gabriel Chapter — and is governed by an elected group of officers collectively known as the Grand Chapter. 

The goals of the Trex Fraternity include the promotion of charity, benevolence, mental improvement, social culture, education, and the strengthening of the bonds of friendship among its members. The Trex Fraternity of California is a non-political, non-religious, non-profit organization.

The Oakland Chapter of the Trex Fraternity was chartered on February 3, 1951 and now stands as the largest chapter in Northern California, with an active roster of 56 members.

A few of the many charities that have received support from the Oakland Chapter over the years include Alameda County Food Bank, Second Harvest Food Bank, Contra Costa-Solano Counties Food Bank, The American Red Cross, Habitat for Humanity, St. Vincent de Paul Society, Boys & Girls Club of Oakland, Fisher House, National Multiple Sclerosis Society, The ALS Association, Today’s Youth Matters, Lincoln Child Center, Encinal High School Band, Oakland Zoo, Echmiadzin Children’s Fund, Western Armenian Athletic Association, the Children’s Fund of Armenia, BAFA, The Armenia Tree Project, and many more.