Otto Eisenschiml (1889-1967) was a prolific author, historian, and expert on the American Civil War. He wrote numerous books and articles on the topic, including:
* The American Civil War: A Pictorial History
* Why the Confederacy Lost
* The Mystery of Lincoln's Assassination
* The Case of the Queen's Necklace
* The Life of an American Patriot: The Biography of John Brown
* The American Iliad: The Epic Story of the Civil War
His works often focused on the lesser-known aspects of the war, the lives of ordinary soldiers, and the political and social context surrounding the conflict. He was also a proponent of using historical documents and primary sources in his research.
While Otto Z Eisner does not appear to be a known author, it is possible you encountered a misspelling or a lesser-known author with a similar name.