WWI "Yankee Division" Shoulder Patch
In September, 1917 a press conference of Boston newspaper reporters was called by General Clarence Edwards to determine a nickname for the 26th Division which had been formed from New England National Guard units. One reporter (Frank Sibley of The Boston Globe) suggested to “call it the ‘Yankee Division’ as all New Englanders are Yankees.” The “Yankee Division” was thus adopted as the nickname of the 26th Division with a “YD” monogram as its insignia.
The “Yankee” Division was the first to copy the French and British system 
of branding all unit vehicles with its insignia. All mules and horses were branded with the “YD” monogram long before the use of Divisional insignia was mandated in the AEF. Motor truck units of the Division also painted sub-unit emblems such as anchors, eagles and replicas of the Bunker Hill Monument (located in Sam’s home neighborhood) on their vehicles.
The wearing of shoulder insignia on the uniform was prescribed for all U.S. Army troops, Corps troops and all Divisions by AEF General Headquarters in the following communication {N. M-674} dated October 20, 1918:
“Each division will adopt and procure immediately some distinctive cloth design which will be worn by every officer and man of the division on the left arm, the upper part to be attached to the shoulder seam. Report will be made to these Headquarters by telegram as to designs adopted in order that there may be no duplication. Approval of design will be made by telegram from these Headquarters.”
In response to this directive, the shoulder patch for the 26th Division was submitted for approval on October 23 consisting of the “YD” monogram in blue cloth matching the color of the French Army uniform on a diamond background of olive drab. The original design was authorized with a subsequent change of the monogram’s color to dark blue. The wearing of this shoulder patch was made compulsory for all men of the 26th Division after November 29, 1918 in orders from First Army Headquarters.
The first shoulder sleeve insignia (such as that pictured above) prior to the Second World War frequently had a make-shift appearance and were manufactured of wool felt-on-felt or other cloth in muted colors. Many of these were very crudely made in the field. Others were embroidered or machine-woven. Later insignia would be mass-produced using full embroidery with a wide range of colors.
When painted helmet markings became widely adopted in the AEF to help identify different organizations, the 26th Division was also the only one to select distinctly different insignia for each unit. Following is a collection of helmets with unique 26th Division unit insignia that have not been lost to history:
101st Infantry Regiment
101st Military Police Battalion
101st Field Artillery Regiment
102nd Infantry Regiment
102nd Machine Gun Battalion
103rd Infantry Regiment
Soldier's Mail
In regards to the YD patches, the first ones available to the units in France were crudely made in France by the soldiers themselves or local seamstresses. I had the honor of interviewing a member of Co.K, 101st Infantry several years ago. At the time he was 102 years old and still recalled clearly much of the war in France. He related to me the story of “Cootie Mary” and how she was the local elder seamstress for his group of fellows and she did the sewing on of the patches when they were approved. She also did repairs on socks, etc. One can only imagine how she got that nickname, knowing that all the soldiers of the YD were inflicted with body lice for most of their time in France. Uniform seams were ripe places for lice. Troops of course were officially deloused at irregular intervals during the war, but “Cootie Mary” probably had no access to this process.