Maria De Fleury was a Baptist—and anti-Catholic—religious, theological, and political polemicist active during the 1780s and 1790s who wrote with force and imagination, especially in her verse. She published one more private poem, an elegiac ode.

The date of MDF's birth is not known. One source lists it as 1754, but this cannot be trusted.

The date of MDF's death is unknown. She was apparently still alive when William Huntington attacked her by name in 1792, but after that no more is heard of her. George Dyer mentions the death of someone named Maria that year, and 1794 has also been suggested.