Final answer:
The exact year the War Department first referenced noncommissioned officer chevrons isn't specified in the provided text, but it implies that traditions like this likely started during the army's earliest years. Significant military changes discussed include racial integration and the introduction of women into service roles in U.S. military history.
Step-by-step explanation:
The first reference to noncommissioned officer chevrons by the War Department isn't specifically mentioned in the provided text. However, the historical context given discusses various aspects of the U.S. military history including racial segregation and the integration of the military, the introduction of women into service, and the professional appearance and uniformity sought by George Washington during the formation of the Continental Army. The focus on uniforms and professionalism suggests that the tradition of using chevrons to indicate rank likely dates back to the army's earliest years under Washington's leadership.
The provided information also details the changes within the military over time, such as the establishment of the Bureau of Colored Troops and the discussions on the treatment and place of Black soldiers in the military, spearheaded by the War Department's Advisory Committee on Negro Troop Policy in 1945, highlighting the racial challenges and the progress that led to the eventual integration of the armed services.