22nd Judicial District Court of Louisiana

St. Tammany Parish is located in the northern region of the New Orleans Metropolitan Area, immediately north of Lake Ponchartrain. The parish seat is Covington, located in the south-central part of the parish. The largest city in the parish is Slidell, located in the southeast part of the parish. One of the largest growing parishes in the state of Louisiana even before Hurricane Katrina, the storm further accelerated growth to the more inland areas of the parish. After Katrina's landfall in August of 2005, the estimated population of the parish was roughly 264,000. Many new residents of St. Tammany Parish due to Hurricane Katrina have come from the southern parishes of Orleans and St. Bernard, where the destruction was greatest.

In 1699, Pierre Le Moyne d'Iberville, a French explorer, became the first European to visit what is known today as St. Tammany Parish. Soon thereafter, St. Tammany was inhabited by various Indian tribes such as the Colapissas, Bayou Goulas, Chickasaw, Biloxi, Choctaw, and Pensacola. After the French-Indian War, St. Tammany Parish became part of English West Florida, just like nearby parishes across the present-day geography of Louisiana, including Washington Parish. West Florida was eventually run by the Spanish after the American Revolutionary War.

In 1810, U.S. President James Madison claimed West Florida as part of Louisiana and sent William C.C. Claiborne to claim the territory. St. Tammany got its name upon being claimed, named after Indian Chief Tamanend. In 1834, the city of Mandeville was founded as a resort town for the people of New Orleans, joining the cities of Covington and Madisonville in the parish. The city of Abita Springs soon followed.

During the 19th and early part of the 20th century, a large railroad connected the cities of Mandeville and New Orleans, which further spurned development of Abita Springs, Covington, and Madisonville. However, the creation of the Lake Ponchartrain Causeway Bridge in 1956, along with U.S. Interstate 12 in 1957, combined with continuous usage of U.S. Interstate 10, relocation and population increases to St. Tammany Parish increased dramatically.