Among the first settlers around Dix were two brothers named Andrews or Anderson, who came from Rome, New York, in 1830. One of them established a post office called "Jordan's Prairie", the name already given to the grassland to the south. Later he platted out a village, which he called "Rome", after his home town. The post office was moved into the village in 1852, and the name changed.
Hiram Milburn of Kell, Illinois moved to Rome between 1853 and 1855. Milburn built a storehouse in 1853 and a hotel in 1854. It is said that, during the construction of the hotel, a wind blew the structure down into a pile, while two men were on the joists, but nobody was hurt. In 1855 Milburn purchased Lewty's Mill and moved it to Rome.
Although Rome Township still exists, the name of the town was changed to "Dix" when the village was incorporated in 1869. There was and still is another Rome, Illinois and the Post Office insisted that the name of this village be changed.
There are several stories as to the origin of the name "Dix". One is that the town was renamed in honor of Gen. John Adams Dix. At the outbreak of the Civil War, Gen. Dix sent a telegram to his agents in New Orleans stating: "If any man pulls down the American flag, shoot him on the spot". Although the telegram was intercepted by Confederate agents and never reached its intended recipient, the text reached the press, and Gen. Dix became one of the first heroes in the North.
Dix is served by the Norfolk Southern Railway. This was built around 1890. The rail line comes from the St. Louis area and turns southeast at Dix. It follows the west side of Casey Creek down to Mt. Vernon.