Rabun was a member of both houses of the
Georgia General Assembly. In 1805, he was elected to the
Georgia House of Representatives, and in 1810, he was elected to the Georgia senate, serving until 1817 as president of the senate. When Governor
David B. Mitchell resigned to accept President
James Madison's appointment as U.S. agent to the Creek Nation, Rabun became governor of Georgia on March 4, 1817. Mitchell replaced
Benjamin Hawkins, who had recently died. Rabun was elected to a full term as governor in November 1817 with the
Democratic-Republican Party. During the
First Seminole War, Governor Rabun called on the
Georgia militia, under the command of General
Edmund Pendleton Gaines, to respond to raids in south Georgia.
Edward F. Tattnall wrote to Governor Rabun about assisting in the raising of a force in the vicinity of the St. Mary's River on March 20, 1817. Rabun ordered two villages to be destroyed for their participation in the raids in south Georgia. By mistake, the Creek village of the Chehaws was burned, and ten Creeks were killed. General
Andrew Jackson, future president of the United States, was enraged, and wanted Captain Obed Wright prosecuted for murder. Rabun rejected the authority of the federal government to intervene in the affairs of a state, especially over a state-controlled militia. He famously remarked to Jackson, "When the liberties of the people of Georgia shall have been prostrated at the feet of a military despotism, then, and not till then, will your imperious doctrine be submitted to." Rabun criticized Jackson for failing to protect Georgia from the Seminoles and the Creeks, creating a bitter rift with Jackson, but endearing himself to the state of Georgia and the state legislature. Rabun was involved in the American Importation Case of 1820 of smuggling slaves into Creek and US territory, in violation of the
1808 law against the American slave trade. John Watson, Deputy Magistrate of Georgia, protested Rabun's interference in the execution of his legal duties in the case of 59 Africans who were allegedly seized under executive orders and later sold. The importation of the Africans and the implication of
David Brydie Mitchell caused wide interest in the case. Rabun commented that anti-slave laws were being constantly violated, and that "high and low were engaging in it". ==Death and legacy==