The word salary comes from the Latin word for salt, which is sal. Specifically, it comes from the Latin term “salarium argentum,” which means “money of salt.” In Roman times, salt was practical as a currency because it was needed for preserving food and was also useful medicinally as an antiseptic. That made it a commodity that had value in every part of the Roman Empire.
It was also a commodity whose trade was closely controlled by Rome and hence it became a very practical currency for paying the various Roman garrisons that peppered the Roman Empire.
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