This article deals with the two books devoted by Luigi Einaudi to the fiscal, economic and social history of the Great War. The author briefly retraces their genesis and construction, shows their systematic connection and illustrates their main historiographical thesis, according to which the cost of the war for Italy consisted in the decline of its already fragile liberal regime. Taking the debate over the taxation of bearer securities as his vantage angle, the author highlights Einaudi’s difficulties in deriving a serene historical narrative from the amalgamation of his earlier writings, often journalistic, but also his reticence and inconsistencies in assessing the economic-financial policy of early Fascism and, more generally, in analyzing the social base of the new regime.