If you are looking for a history or analysis of the epic battle of Verdun from a military or fighting standpoint, this is not the work for you. You will be better informed by Alistair Horne's classic "The price of glory" or Malcolm Brown's "Verdun 1916".
Ian Ousby takes a look at Verdun through a rather different lens. He concentrates on the rhetoric and symbolism of France and its relations with Prussia/Germany, and concludes that these things had an enormous bearing on the path that led to and sustained such an awful battle. The very experiences and emotions of men who were there were shaped not only by their physical experience of battle, but by their attitudes and limitations of expression that were influenced by such rhetoric.
The history of the battle itself is given only in outline, although the opening bombardment and attack and the surprisingly easy capture by the Germans of Fort Douaumont are give some deeper attention. The entirety of the battle and its phases are subsumed into one, endless, merged mass of unspeakable horror, fuelled by the many personal memoirs, letters and notes that appear to form the bulk of the author's research.
The enduring symbols of the battle, from Petain's "On les aura" to Nivelle's "Ils ne passeront pas", to the Tranchee des Baionettes, the crushed concrete of the forts and the nine villages that were never rebuilt, are all analysed and take their place in the new set of legends and myths that Verdun created for itself. Ousby does not go on to comment on how those myths formed the basis for new and inappropriate conclusions that led directly to ignominy and feat in 1940, but the reader can easily pick out the strands.
The major failings for me are the almost total absence of the German viewpoint and experience, and the reduction of Joffre to a rather boneheaded individual merely bleating for resources for his Somme offensive.
Having said that, I found this a useful work and for the most part a fascinating read. There are some central passages on long-past French history, nationalism and racism that I found slow and at one point almost made me give up, but the pace and focus on the battle itself picks up again and by the conclusion I was glad that I persisted with it.
If I was asked for advice about what to read in order to develop some understanding of French attitudes and politics at Verdun, I would place this second to Horne's "The Fall of Paris: the siege and the Commune, 1870-71 ".