Harriet Lane was the niece to James Buchanan, and served as his First Lady during the years prior to the Civil War that he was in office as President of the United States. She was a young First Lady and very fashionable.
James Buchanan's home, Wheatland, is located in Lancaster, Pennsylvania - my hometown. My mother and I have worked and volunteered there throughout the past 10 years. It's a lovely museum. I even got to portray Harriet Lane on several occasions. :)
Here are a few pictures of a beautiful ballgown that she wore. Isn't her hair styled perfectly! She was supposed to be quite a beauty in her time.