An excellent resource.

I was little disappointed when I read the people's history, however. When I read it, the first couple of chapters were spotted with factual errors. I found that disappointing. Nonetheless, it makes a good counter point to the rah-rah history that troubles most textbooks.

This really got me into the horrors of the Civil War (as well as all wars).

The movie was pretty good too.

Beautiful & humanistic way of viewing an inhumane era

You can't fully do one without investing in the other

Against the Grain by James C Scott
1491 by Charles C Mann
A Distant Mirror by Barbara W Tuchman
The Great Influenza by John M Barry

The compelling analysis of the most terrifying trend in modern European History during the 20th Century and its origins.

Others:

Bernard Fall, The Two Vietnams, a Political and Military Analysis
I.F. Stone, The Hidden History of the Korean War 1950-51
Adam Tooze, Wages of Destruction (an economic History of Nazi Germany)
Jared Diamond, Guns, Germs and Steel
Charles C. Mann, 1491
James Bradley, The China Mirage
Stephen Kinzer, The True Flag (T. Roosevelt, Mark Twain and the Birth of the American Empire)

Some may argue that one or more of these are not really "history" books, but I considered all them representative of useful methods or tools for a historian. This is in contrast to the scores of historical works that I have read and forgotten over a lifetime.

Gore Vidal's "Burr". I read this novel as a teenager and it completely changed the way I viewed our nation's founders, especially George Washington and Thomas Jefferson, and how I viewed the study of history itself.

History text books at the time tended to deify the founding fathers, especially the aforementioned Washington and Jefferson. Gore Vidal takes each down several pegs in his novel and helped show them (albeit a bit crudely at times) as the flawed human beings they really were, all through the eyes of Aaron Burr somewhat reimagined by Vidal as an equally flawed antihero.

Along with Burr, Vidal's other novels such as "Lincoln" and "1876", also helped shaped how I viewed the study of history as a discipline. No longer did I see history as merely being a dry and lifeless recitation of facts etched in equally dry and lifeless granite, but as something dynamic and assuredly open to the interpretations of those who have recorded and studied it through time. I became fascinated with the historiography behind the history.

At any rate, it seems odd in retrospect that a work of historical fiction would help turn me into the sort of person who sometimes obsesses over the historiographical veracity of the history books he reads.