Namesakes
Fictional Characters from Books:
2 characters
Henrietta Musgrove 1818 Persuasion 
Henrietta Petowker 1839 Nicholas Nickleby
Fictional Characters from Song Titles:
1 character
(character) Henrietta 2012 Henrietta
Fictional Characters from Television:
1 character
Etta Bishop 2008 Fringe
Notable Scientists and Inventors:
1 astronomer
Henrietta Swan Leavitt 1868-1921
Other Royalty:
1 princess
Isabella of Denmark (a.k.a. Henrietta) 2007- Denmark