The pre-war novels of George Orwell, which were realistic unlike his post war ones. In particular, Keep the Aspidistra Flying and Coming Up for Air make one glad not to live in the 1930s. All of his non-fiction stuff would serve the same purpose.
It’s been said that her work on “The Rape of Nanking” (which included interviews with many survivors) had contributed to the author’s depression and eventual suicide.
Born Red: A Chronicle of the Cultural Revolution by Gao Yuan
Man Is Wolf to Man: Surviving the Gulag by Janusz Bardach and Kathleen Gleeson
I Was Saddam’s Son by Latif Yahia
The Whisperers: Private Life in Stalin’s Russia by Orlando Figes
The Forsaken: An American Tragedy in Stalin’s Russia by Tim Tzouliadis
The Grapes of Wrath
John Dos Passos’s “U.S.A. Trilogy”
Michael Herr’s “Dispatches”
Mailer’s “The Naked and the Dead”
The Endless Steppe by Esther Hautzig. It’s a memoir about how her family was exiled to Siberia just before World War II. It’s written for children, but still very powerful, with many interesting details about how they survived.
Barrayar by Lois McMaster Bujold. An adult SF novel about a civil war on another planet.
In the great explorers category: From the Cape to Cairo - The First Traverse of Africa from South to North by Ewart S. Grogan & Arthur H. Sharp.
In the late 1890’s, young Ewart fell in love with Gertrude, her stepfather did not approve, Ewart decided to prove himself by walking the length of Africa. It wasn’t easy.
I’m now reading Empire of the Summer Moon: Quanah Parker and the Rise and Fall of the Comanches, the Most Powerful Indian Tribe in American History. The Comanches used their absolute mastery of fighting on horseback to rule vast stretches of the plains–including most of what is now Texas. They fought against other tribes (including the gentle Apache), Spaniards, Mexicans, Texans & the US–committing acts of unusual cruelty in a cruel world. Yet Cynthia Ann Parker, kidnapped daughter of settlers & mother of Quanah, preferred her life as a Comanche to life after her “rescue.”
It’s a fascinating book but tough to read. Hard men (& women) on both sides…
For pre-WW1 Europe, try The Fall of Paris: The Siege and the Commune 1870-71 by Alistair Horne.
People eating cats and zoo animals, daring escapes by hot air balloon, pigeon post, Bismarck, Victor Hugo, Krupp artillery and of course the short-lived Commune. A very interesting time indeed.
I heartily recommend this one, having read it earlier this year and I would add the two other books of his French trilogy : The Price of Glory about the battle of Verdun and To Lose a Battle about the battle of France, 1940.
Maybe a bit too broad for your specified interests, but The Fiftiesby David Halberstam was outstanding - a remarkable (and thoroughly enjoyable) work on a most interesting decade.