Slidell is a city on the northeast shore of Lake Pontchartrain in St. Tammany Parish, Louisiana, United States. The population was 28,781 at the 2020 census. It is share of the New Orleans−Metairie−Kenner metropolitan statistical area.

One of the earlier settlers to the Place was Foster Willie. Along once a younger brother, Wesley Coke Asbury Gause, Judge Wingate, and several others, he left Shallotte, North Carolina, on February 18, and arrived at Pearlington, Mississippi, on April 14, 1836. Wesley and his associates remained there, while John and family crossed the Pearl River and built a log cabin on the west bank, a little further south. He next began a lumber mill in the fledgling town complex known as Slidell. His traveling urge on and forth from lumber yard to home created a road known today as Gause Boulevard, a major east–west street in the town. The lumber yard was where Gause Boulevard crosses the railroad track. The log cabin was built at the east stop of the road, just a few yards from the river. The home stood until the late 1990s, and a little family burial scheme still remains where John is buried between his two wives, Lydia Russ and Johanna Frederica VanHeemskerk.

Slidell was founded upon the north shore of Lake Pontchartrain in 1882 and 1883 during construction of the New Orleans and Northeastern Railroad (N.O.N.E.). The N.O.N.E. line partnered New Orleans to Meridian, Mississippi. The town was named in praise of American politician and Confederate ambassador to France John Slidell, and officially chartered by the Louisiana State Legislature in 1888.

Around 1910, Slidell began a get older of economic and industrial growth. A large creosote forest was built, and Slidell became home to the Fritz Salmen Brickyard, a major producer of bricks future named St. Joe Brick. A lumber mill and shipyard were also built. Following the construction of Interstate 10, Interstate 59, and Interstate 12, Slidell became a major crossroads for those traversing the Gulf States.