The book "George B. McClellan's Mexican War Diary" by George B. McClellan is a unique account of the military events that took place during the American-Mexican War in the 19th century. This diary reflects the feelings, thoughts and memories of a famous American military figure who later became a general and politician. The book allows the reader to better understand the strategy and tactics of the American army, as well as the military art of that time through the lens of the author's personal experience. The Mexican War Diary of George B. McClellan is a valuable resource for historians, students, and anyone interested in military history and the lives of notable individuals.