The origins of the Information System Technology (IT) rating goes back to more than a century.
Regardless of the time period of this rating, communications and information flow was the foundation.  Today, this rating is fundamental to Assured Command and Control, Battle Space Awareness and Integrated Fires, which is the core mission of the Information Warfare Community and the cornerstone to the warfighter.

Because of the work of James Maxwell, Heinrich Hertz and Guglielmo Marconi during the mid to late 1800s, the Navy moved into the “information age” of that day and established the first Radio Station in the Pearl Harbor area on October 1, 1906.  However, it was not until 15 years later that the navy established the radiomen rating in 1921 to operate and maintain this new amazing wireless technology.

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Radiomen standing the watch

From the very beginning radiomen served on all navy ships and shore commands.  They were responsible for operating radios, radio direction finders, teletypewriters and facsimile equipment.  They transmitted and received messages in international Morse code, radio printer and by voice circuits. Additionally, they were responsible for maintaining their radio equipment and antennas.

Wireless communications were expanding.  Not only was the United States using this new technology so were the Japanese, Russians, Germans, British and many other militaries. As a result of a growing threat a couple of years after the radiomen rating was established, a small group of selected senior radiomen were trained to intercept Japanese Katakana radio communications that produced radio intelligence.  Known as the On-The-Roof gang, these radiomen eventually became Communication Technicians (CT) in 1948 and then the rating name changed to Cryptologic Technicians (CT) in 1976.  However, the majority of radiomen at the time were communicators that were not involved in radio intelligence.

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International Business Machine (IBM) Operator, circa 1940

With a need to better calculate gun trajectories, ensure accurate accounting, and handle mass logistics, the Navy turned to IBM tabulating equipment during WWII. The move gave birth to a new rating called International Business Machine operator.  This was probably the only time a Navy rating had been named after a private corporation. This rating, however, only existed for about a year before the specialist rating, Punched-Card Accounting Machine Operator, was established.  This rating was an ad hoc response to the immediate need for personnel whose skills became particularly necessary with the outbreak of war in 1941.

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Grace Murray Hopper (seated, second from right) and Howard Aiken (seated, center), along with other members of the Bureau of Ordnance Computation Project, in front of the Harvard Mark I computer at Harvard University, 1944.

In 1944, IBM introduced the nation’s first large-scale electromechanical calculator (the automated sequence controlled calculator or the “Harvard Mark I”) that was used by the U.S. Navy Bureau of Ships.  This new rating was crucial in the operation of this system.

Giant “calculator” (the Mark I computer) solves mathematics problems at Harvard U…HD Stock Footage

In 1948 the navy combined the Punched Card Accounting Operators and Key Punch (Operators and Supervisors) specialist ratings to establish the Machine Accountants (MA).  Experts in machine-accounting procedures, the MA rating responsibilities included operating accounting machines and maintaining key-punching and key-verifying equipment to record statistical data on tabulating cards. They also prepared routine and special reports based on the information they received and analyzed. Typically, MAs served on large ships and shore stations.

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Data Processing technician (DP) rating badge

In 1967, the MA rating name and designation was changed to Data Processing technician (DP).  The DP rating was responsible for operating and maintaining transceivers, sorters, collators, reproducers, interpreters, alphabetic accounting machines, and digital electronic data processing machines for accounting and statistical purposes. They were used extensively to operate accounting systems in order to maintain personnel records, keep tabs on the receipt and transfer of supplies and disbursement of money as well as to keep track of all equipment the Navy owned.

As the technology changed, so did the jobs of the DP rating. Because their work moved into the realm of information and communication systems rather than simply processing data for computer manipulation the Navy on October 1, 1997 disestablished the DP rating and merged the rating into the radiomen rating.

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Information Systems Technician 2nd Class Hendra Samuel from Wayne, N.J., checks for a shipboard to shipboard circuit in the joint message center (JMC) shop aboard USS Iwo Jima (LHD 7).

In November 1999, the radiomen rating name was changed to Information Systems Technician (IT), and on March 1, 2006, the Cryptologic Technician (Communications) CTO rating was disestablished and merged into the IT rating.

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Seaman Jacob Elsbree, an information systems technician student, practices basic computer hardware configuration at Information Warfare Training Command Corry Station, July 26, 2016

Today, the manning for the IT rating is over 11,000, one of the largest in the Navy. This historic rating of the 21st century operates and maintains the Navy’s global satellite telecommunications systems, mainframe computers, local and wide area networks, and micro-computer systems used in the fleet. Administrative support is also provided with the operation of automated equipment that keeps records of personnel training, disbursement, health, assignments and promotions within the Navy. They ensure the all-important communications link between units at sea and stations ashore.  Like the radiomen rating of the past, today’s IT rating serves on all navy ships and shore commands.

Sources:
uniforms-4u.com
news.usni.org
navydp.com
The BLUEJACK’s Manuals 1944, 1950, 1978
http://www.public.navy.mil