Insignia
The insignia of the 1st Infantry Division originated in World War I. There are two theories as to how the idea of the patch came about.
The first theory states that the 1st Division supply trucks were manufactured in England. To make sure the 1st Division's trucks were not confused with other allies, the drivers would paint a huge "1" on the side of each truck. Later, the division engineers would go even farther and put a red number one on their sleeves.
The second theory claims that a general of the division decided the unit should have a shoulder insignia. He decided to cut a red numeral "1" from his flannel underwear. When he showed his prototype to his men, one lieutenant said, "the general's underwear is showing!" Offended, the general challenged the young lieutenant to come up with something better. So, the young officer cut a piece of gray cloth from the uniform of a captured soldier, and placed the red "1" on top.
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