Leonora Mary Hassal Sansay (also: Leonora Sansay, Mary Hassall, Hassal or Hassell) (b. 1781) U.S. Vice President Aaron Burr's niece, (purportedly) wrote a series of letters from Le Cap to him, describing the situation in Saint-Domingue at the time of the Haitian Revolution. The letters were collected in a book entitled Secret History, or, The Horrors of St. Domingo: In a Series of Letters, Written by a Lady at Cape Français to Colonel Burr, Late Vice-President of the United States. The book covers the time span from 1802 until post-revolutionary Haiti under Jean-Jacques Dessalines in 1805.
"At the outset I called these the "purported" letters of Mary Hassal. Perhaps they were really letters. But I get the distinct impression that they were written during one concentrated writing time, and not as letters over a long period. The letters have too much continuity. Each picks up exactly where the last one has ended, and the lead-ins to new stories is too perfect. Added to this are the last series of letters which are not only Mary Hassal's letters to her sister in Cuba, but her sister's letters back to her. It works too much like a novel. Perhaps they were just heavily edited letters.
- Hassal Mary (1808). Secret history, or, The horrors of St. Domingo. Philadelphia: Bradford & Inskeep; R. Carr, Printer.
- Hassal, Mary, (1971).SECRET HISTORY, Written by A Lady At Cape Francois Books For Libraries Press, Freeport, NY, ISBN 0-8369-8832-9