The Old St. Gabriel Catholic Church, which appears outwardly to be a fairly typical 19th century Gothic revival church, is in fact a 19th century remodeling of a much older French colonial structure, built ca. 1709 by Acadian immigrants from the vicinity of Les Mines in Nova Scotia (Acadie).

The church was built originally on a land grant of one arpent frontage by forty arpents depth issued on August 18, 1767 by Don Antonio Ulloa, governor of Spanish Louisiana. The original site was approximately two miles upstream from the present location of the church, as shown on an undated map in the Biblioteca Nacional in Madrid, which has been estimated to date from between 1767 and 1769.

In 1772 or thereabout, the church was disassembled and rebuilt at a different site. Presumably, this is the present site, although no documentation has been found to prove this. The reasons for the relocation are not known.

The church has been moved back at least three additional times, in 1818 and 1932, all on the present site, as the Mississippi River changed its course, threatening the building. The exact building location of ca. 1772 is now probably somewhere in the river itself.

The church has undergone only one major renovation, in the 19th century, when it was converted from a French colonial building to a Gothic revival building. The date of this modernization is not known; however, church records do refer to a major renovation during the 1887 move, which may have been the date of the Gothic restyling.

In the 19th century renovation, the original hipped roof was changed to a gabled roof, the original bell tower was removed and a new tower built over the west entrance. The original shallow arched ceiling was cut out and a higher vaulted ceiling installed. New turned wood columns were installed to support the ceiling vault and tie rods were installed to prevent the walls from spreading. A 12 foot extension was added at the east end of the church, providing a sanctuary with sacristies on either side. The original windows were replaced with taller arched lancet windows. The original featherboard siding was replaced with clapboards, and the original 1X12 flooring was overlaid with new 1X4 tag flooring.

All of the original woodwork is of cypress, exhibiting a high degree of workmanship in its joinery. Many of the 19th century members are of pine and their joinery is somewhat cruder by comparison.