Final answer:
The position of Sergeant Major of the Army was established in the year 1966 as a senior non-commissioned officer rank and role in the United States Army.
Step-by-step explanation:
The position of Sergeant Major of the Army was established in 1966.
The Sergeant Major of the Army is a unique non-commissioned officer rank and position in the United States Army. The holder of this post is the senior enlisted advisor to the Army Chief of Staff, and they play a critical role in representing enlisted soldiers' perspectives. This position was not one of the original positions created at the birth of the United States Army; rather, it was established in the 20th century.
During the time of the Civil War or the founding of the country, various non-commissioned officer ranks existed, but the specific position of Sergeant Major of the Army, as we know it today, did not. The creation of this position was part of a broader move to professionalize the enlisted ranks and ensure that their interests were represented at the highest levels of Army leadership.