The Spanish governor, Bernardo de Gálvez, named it in honor of his wife, Marie Felicité.

[4] It was greatly enlarged and improved under the administration of Dr. John Welch Jones, who was appointed as superintendent in 1874, during the Reconstruction era.

The bi-racial legislators in power at the time made commitments to public education and state welfare institutions.

[6] At the 2019 American Community Survey, there were 19,371 people living in the parish, down from 20,267 at the 2010 United States census.

The 2019 census-estimated population comprised 6,959 households living in 8,487 housing units spread throughout the parish.

[13] By the 2020 United States census, there were 19,539 people, 6,959 households, and 4,777 families residing in the parish.

[13] During the 2020 census, the parish's race and ethnic composition was 58.3% non-Hispanic white, 36.38% Black and African American, 0.31% Native American, 0.24% Asian, 0.05% Pacific Islander, 2.63% other or multiracial, and 2.0% Hispanic or Latino of any race.

[12] As of 2019-2021's census estimates, approximately 40% of the population was employed in the parish, and the home-ownership rate was 80.5%.

[16] Silliman Institute in Clinton was established in the late 1960s as a directed response to federal courts ordering the desegregation of the East Feliciana public school system.