Tattnell was a son of Joseph Tatnall, a miller and banker in Wilmington.
He was a director of the Delaware and Maryland Railroad and of the Wilmington and Susquehanna Railroad, two of the four railroads that helped build the first rail link from Philadelphia to Baltimore. In 1838, they merged into the Philadelphia, Wilmington, and Baltimore Railroad. His service is noted on the 1839 Newkirk Viaduct Monument (upon which his name is misspelled as "Tatnell").
- Jordan, John Woolf (1911). Colonial Families of Philadelphia, Volume 2. Philadelphia: Lewis Publishing Company. pp. 1526–27.
- Wilson, William Bender (1895). History of the Pennsylvania Railroad Company with Plan of Organization, Portraits of Officials and Biographical Sketches. 1. Philadelphia: Henry T. Coates & Company. pp. 296–299. Retrieved November 25, 2012.
- "Records of Vice President Henry Tatnall, 1897–1940 Pennsylvania Railroad". ArchiveGrid. WorldCat. Retrieved October 10, 2013.