While LA 9 changes its general trajectory by turning northeast at Homer toward Junction City, Route 12 continued northward along the present path of US 79 to the Arkansas state line via Haynesville. US 79 was placed onto the existing state highway route upon its creation in 1935, and the two remained concurrent through the pre-1955 era. However, in the 1955 Louisiana Highway renumbering, unnecessary concurrencies between U.S. and state routes were eliminated, and the LA 9 designation was instead continued along a different pre-1955 state route north of Homer.