The Octofoil shoulder patch of the 9th Infantry Division dates from the 15th Century when it was customary for each son in a family to have an individual mark of distinction. Under the rules of heraldry there are eight foils or positions. The Octofoil went to the ninth son, symbolic of him being surrounded by eight brothers. The symbolism of the Octofoil makes it a logical and correct insignia for the 9th Infantry Division. The red quaterfoil of the patch alludes to the Artillery, while the blue one represents the Infantry.