Located north of New Orleans, the town's name is pronounced locally as "Frank-lin-ton".
A Franklinton physician, Jerry Thomas, represented Washington Parish in the Louisiana House of Representatives from 1988–1999 and then served from 1999-2004 in the District 12 seat in the state senate, having succeeded Phil Short of Covington, who resigned. Dr. Thomas was the Washington Parish coroner from 1980-1988.
Franklinton was founded in 1819, originally under the name of Franklin, but in 1826 the name was changed to Franklinton since there was already another town with the same name in St. Mary Parish. In 1826, representatives and citizens from both communities showed up at the state capitol in Baton Rouge to state their cases to keep the name "Franklin". A compromise was reached by the Louisiana Legislature, allowing Franklin in St. Mary Parish to retain its name, while Washington Parish's parish seat would be known as Franklinton.
Franklinton became the parish seat of Washington Parish on February 10, 1821, two years after the parish was carved out from St. Tammany Parish.
Much of Franklinton, as well as most of Washington Parish, sustained damage from Hurricane Katrina in 2005.
On January 11, 1935, a small group of men forced their way into the Washington Parish jail in Franklinton early on January 11, shot and beat an African American man convicted of murder to death, dumped his body alongside a lonely road three miles (5 km) from town and dispersed. The man had been tried, convicted and sentenced within ten days of his arrest. The body of the victim, Jerome Wilson, 30, was found on the road two hours later. Wilson was convicted in August of slaying Deputy Sheriff Delos C. Wood in a gun fight on the Wilson place. Aroused from his cot, the terror stricken man pleaded for mercy. His pleas were followed by screams for help. Then a bullet was fired into the back of his head. Officers expressed the belief that the man was shot because his cries would arouse parish authorities, who twice had thwarted attempts to lynch him. The body was dragged to a waiting car. Five days earlier a new trial was granted to Wilson by the Louisiana Supreme Court on the grounds that the defendant had not received a fair trial. The decision cited that he was tried, convicted and sentenced within ten days of his arrest.