Shoulder insignia, the brightly colored designs worn on the left sleeve below the shoulder to denote division, corps, armies, or organizations within the U.S. Armed Forces, express a warmth and a fraternity which men of all services known from experience. Originated by the 81st Division in 1918, the cloth patches were soon officially recognized for their value in building morale.
I found this document in my mother-in-law personal papers after she passed away. Thank you Stephanie for saving this.
Source: Sunday August 1, 1954, The Philadelphia Inquirer