While Von Steubon outlined the duties of such NCOs as the Sergeant Major, Quartermaster Sergeant and other key NCOs it was the Company First Sergeant, the American Equivalent of the Prussian Feldwebel, that he directed most of his attention. This noncommissioned officer, chosen by officers of the company, was the linchpin of the company and the discipline of the unit. The conduct of the troops, their exactness in obeying orders and the regularity of their manners, would "in a large measure, depend upon the First Sergeant's vigilance." The First Sergeant therefore must be "intimately acquainted with the character of every soldier in the company and should take great pains to impress upon their minds the indispensable necessity of the strictest obedience as the foundation of order and regularity." Their tasks of maintaining the duty roster in an equitable manner, taking "the daily orders in a book and showing them to their officers, making the morning report to the captain of the state of the company in the form prescribed, and at the same time, acquainting them with anything material that may have happened in the company since the preceding report," all closely resembled the duties of the 17th century company sergeant.
The First Sergeant also kept a company descriptive book under the captain's supervision. These descriptive books listed the names, ages, heights, places of birth, and prior occupations of all enlisted in the company. The Army maintained the books until about the decade of the 20th century when they were finally replaced by the "Morning Report."
Since the First Sergeant was responsible for the entire company, he was, in Von Steuben's words, "not to go on duty, unless with the whole company, but is to be in camp quarters to answer any call that may be made."
On the march or on the battlefield, they were "Never to lead a platoon or section, but always to be a file closer in the formation of the company, their duty being in the company like the adjutant's in the regiment."
In the Army and Marines, the first sergeant is often referred to as "Top," or "Top Kick." The nickname has obvious roots in that the first sergeant is the "top" enlisted person in the unit, and a "kick in the pants" is a motivation tool (not literally, at least in today's military) to get the troops into gear.