NAVMCP_170415_08
Existing comment: Post-Civil War Petty Officers
First There Were Firsts

Prior to the Civil War, enlisted Sailors were either petty officers or seamen. There were no classes within either group. After the Civil War, the Navy began distinguishing petty officers based on their perceived value to the Navy.
In 1866, petty officers were divided into two groups, Line and Staff. Each group wore a distinctive petty officer's device. Line Petty officers were considered to be the most important petty officers. Later in 1869, Navy Uniform Regulations authorized Master-at-Arms, Yeomen, Surgeon's Stewards, and Paymasters to wear "blue jackets with rolling collars, double breasted; two rows of medium size navy buttons..." and "plain blue caps with visor..." All other petty officers were directed to wear four cuff marks instead of three.
Petty Officers were divided into three classes in 1886. All first class petty officers were directed to wear blue jackets and caps with visors to distinguish them from other petty officers and seamen. Master-at-Arms were the most important first class petty officers. They had the most authority and were he highest paid petty officers in the Navy. Master-at-Arms of the late 19th century were senior enlisted leaders and can be compared, in some ways, to shipboard Command Master Chiefs today.
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