Start with high-confidence literature & history books, then narrow by subgenre or adjacent topics.
Homage to Catalonia (collins Classics)
George Orwell
Exile's Return
Malcolm Cowley, Donald W. Faulkner
Worlds Apart
Benjamin Paloff
The Hitler of History
John Lukacs
On the Natural History of Destruction
W.G. Sebald, Anthea Bell
Eminent Outlaws
Christopher Bram
The Scars We Carve
Allison M. Johnson
The Smart Words and Wicked Wit of Winston Churchill
Max Morris
Review of Mein Kampf by Adolf Hitler
George Orwell, Andrea Karola