According to the United States Census Bureau, the CDP has a total area of 8.8 square miles (23 km2), of which 7.8 square miles (20 km2) is land and 1.0 square mile (2.6 km2) (11.79%) is water.
History
In 1682, La Salle recorded the presence of a village of Quinipissa peoples in the vicinity of modern-day Hahnville. In the 1700s, German immigrants to the French colony of Louisiana began settling along the Mississippi upriver from New Orleans in what became known as the German Coast. In the early 1800s, following the sale of Louisiana, the United States established the St. Charles Courthouse in the area and a small community grew up around it. In February 1872, Thomas Sharpe began laying out a village near the courthouse, which he called Flaggville after district judge Othelle J. Flagg. Around the same time, former governor Michael Hahn, who had a sugar plantation upriver from Flaggville, began dividing his land to found Hahnville. Gradually "Hahnville" became the commonly accepted name for the larger area.[5][6][7]
^Joseph G. Dawson (1 January 1990). "Michael Hahn". The Louisiana Governors: From Iberville to Edwards. Louisiana State University Press. pp. 148–152. ISBN 978-0-8071-1527-5.
^"Hahnville High School" (Archive). AdvancED. p. 4/9. Retrieved on December 3, 2016. "Hahnville High School services all students on the west bank of the Mississippi River in St. Charles Parish, including the communities of Ama, Boutte, Hahnville, Luling, Paradis, Des Allemands.
