Their original function was representing U.S. citizens seeking reimbursement for having their horses and livestock commandeered by Union forces during the Civil War

Enrolled agents date back to the late 19th century, although they would not take on that title for another eight decades.

Their original function was representing U.S. citizens seeking reimbursement for having their horses and livestock commandeered by Union forces during the Civil War. After the income tax was instituted in 1913, these agents could represent citizens before the government on tax matters.

In 1959 a special enrollment exam was created to qualify representatives before they could represent taxpayers before the IRS. In 1966, the Treasury Department began using the Enrolled Agent (Enrolled to Practice before the IRS) title for the professionals it licensed.