My favorite non-fiction reads were "Frederick W. Lander, The Great Natural American Soldier," by Gary Echelberger; Echelberger was really kind and helpful in my Aiken research when I found that Aiken and Lander were friends and fellow spies; and
"In The Hands of Providence Joshua Lawrence Chamberlain and the American Civil War," by Alice Rains Trulock.
But c'mon, I know you all are really smart, but don't you ever read fiction?
My perennial favorites (that I usually re-read every year):
"These Is My Words" by Nancy Turner and
"The Guernsey Literary and Potato Peel Pie Society" by Mary Ann Shaffer and Annie Barrows
Oh, and anything Jane Austen

I was THRILLED when my 15 year old (who I had to pay to read books just last year) asked for the complete collection of Jane Austen books from Santa. One wish I'm happy to oblige