The Southern Sentinel of Plaquemine, Louisiana, began publication in August 1848. Its owner and editor, William Plummer Bradburn (ca. 1815-1864) was a native of Tennessee, who began his newspaper career as an apprentice at the National Banner and Nashville Daily Advertiser [LCCN: sn86071170]. He ran away from this position in 1832, eventually joining the navy. In 1842, Bradburn purchased the Ibervillian from John Dutton in Iberville Parish, Louisiana, a wealthy region known in the 19th century for its sugar plantations. In 1844, having unsuccessfully attempted to claim the Mexican estate of his late uncle Juan Davis Bradburn (a general in the Mexican army), Bradburn began publishing the La Grange Intelligencer [LCCN: sn86088857] in what was then the Republic of Texas. Three years later, Bradburn returned to Louisiana and edited several New Orleans newspapers before settling permanently in Iberville Parish, where he became the managing editor of the Southern Sentinel in 1848.
A Whig newspaper, the Sentinel endorsed Louisiana planter and Mexican-American War hero Zachary Taylor in the presidential election of 1848. In 1852, it supported another veteran of the war, Winfield Scott, and, in 1856, former president Millard Fillmore. Articles frequently discussed the leading political issues of the day, including abolition, the Free Soil movement, the Compromise of 1850, and the Fugitive Slave Act. The activities of Whig Party leaders Henry Clay and Daniel Webster were reported at some length. National and international news was of a general nature, while local news tended to focus on political organizations and meetings.
The Sentinel was briefly published twice a week in four pages, with three in English and one in French, before becoming a four-page English weekly with French content limited mostly to advertisements. In 1858, the paper merged with the Iberville Gazette [LCCN: sn83016703] to form the Gazette and Sentinel [LCCN: sn86053832].