AIn The Downfall Zola tells the story of a terrific land-slide which overwhelmed the French Second Empire: It is a story of war, grim and terrible; of a struggle to the death between two great nations.
In it the author has put much of his finest work, and the result is one of the masterpieces of literature.
The hero is Jean Macquart, son of Antoine Macquart and brother of Gervaise. After the terrible death of his wife, as told in "La Terre" (The Soil), Jean enlisted for the second time in the army, and went through the campaign up to the battle of Sedan. After the capitulation he was made prisoner, and in escaping was wounded. When he returned to active service he took part in crushing the excesses of the Commune in Paris...
The Downfall has been described as "a prose epic of modern war," and vast though the subject be, it is treated in a manner that is powerful, painful, and pathetic.
More info about the Rougon-Macquart series at Wikipedia.