With a population of 23,515 at the 2020 census,[1] the parish seat is Pointe à la Hache and the largest community is Belle Chasse.

The name "Plaquemines," in French Creole, was derived from the Atakapa word piakimin, meaning the local fruit persimmon.

The French used it to name a military post they built on the banks of the Mississippi River, as the site was surrounded by numerous persimmon trees.

The oldest European settlement in the parish was La Balize, where the French built and inhabited a crude fort by 1699 near the mouth of the Mississippi River.

The name in French meant "seamark", a tall structure of wood built as a guide for ships.

The pilots moved upriver and built the settlement they named Pilottown, which reached its peak of population in the 19th century.

[6] The river pilots' expertise continues to be critical, but now they generally live with their families in more populated areas.

In 1861, Fort Jackson served as an important Confederate defense for the city of New Orleans during the Civil War because it was at the mouth of the Mississippi River.

Because Plaquemines Parish encompasses the last 70 miles (110 km) of the Mississippi River before it reaches the Gulf of Mexico, it is the site of several oil refineries, which rely on the shipping lanes for moving their product.

Plaquemines Parish was the first place in the United States where shippers used a container for cargo in foreign trade.

From 1924 to 1969, Plaquemines and St. Bernard parishes were effectively the domain of the Democratic political boss Leander Perez, who established a strong hold over the area.

[7] The Civil Rights struggle for African-Americans to become registered voters in Plaquemines Parish began in October 1946, under the guidance of Dr. Rev.

With the aid of Attorneys Earl Amedee and Louis Berry from New Orleans, Griffin and twenty-six African-Americans from Plaquemines Parish organized the Plaquemines Parish Civil and Political Organization, Inc., to fight racial barriers established by Perez.

[8] The organization filed class-action suits against Leander Perez and in 1953, several African-Americans became registered voters in Plaquemines Parish.

[10] The Great Hurricane of 1915 devastated much of the parish, with multiple levee breaches on both sides of the Mississippi, a 12-foot storm surge, and hundreds of deaths.

[11] The old Parish Courthouse in Pointe à la Hache was among the many buildings destroyed in the storm, but a new one was completed within the year.

This action resulted in the flooding of much of the less populated St. Bernard and Plaquemines parishes, causing widespread destruction to agriculture and housing.

[13] No place escaped without some damage, while most of Plaquemines, Orleans, and neighboring St. Bernard parishes was severely affected.

The towns of Pointe à la Hache, Port Sulphur, Buras, Triumph, Empire, Boothville, Phoenix, and Venice suffered catastrophic damage.

Amid heavy rains accompanied by hurricane-force winds in excess of 120 mph (190 km/h) at initial landfall (with a Category 5 storm surge), the levees failed and broke.

[citation needed] It is estimated that without significant human intervention, Plaquemines Parish will lose 55% of its current land to rising sea levels over the next 50 years.

Communities not listed below include Happy Jack, Myrtle Grove, Nairn, Naomi, Oakville, and Scarsdale.

Males had a median income of $49,251 versus $36,404 for females; 18.2% of the parish population lived at or below the poverty line.

Plaquemines also has a vibrant citrus and horticulture nursery stock industry, but saltwater intrusion is becoming a hurdle to these producers.

Plaquemines has a huge potential for hydrokinetic energy sites along deep bends in the Mississippi River.

In 1952 it was the most Republican county-equivalent in the nation,[39] and until the decay of the Perez machine no Democrat was to pass thirty percent of the parish's vote.