Scholars have not yet provided an authenticated explanation of Britain's support for the League of Nations against Mussolini's scheme to annex Ethiopia in 1935. Writing during the Italo-Ethiopian War and its immediate aftermath, A. J. Toynbee concluded that the Peace Ballot was responsible, a verdict followed by the two principal Italian historians of the war's diplomatic preliminaries, L. Villari and G. Salvemini. Their judgment was echoed by the author of the pioneer work on interwar British history, C. L. Mowat, and no doubt was cast on this version until 1961. Even then no credible alternative was advanced by the dissenter, A. J. P. Taylor, and in the more recent first full-scale diplomatic history of the conflict's origins, the American, G. W. Baer, has drawn substantially the same conclusions as his European predecessors, A. J. P. Taylor apart.
Villari worked from unpublished (still) Italian documents; Salvemini augmented these selections with a vast array of press material and other contemporary printed sources. When Mowat published his book two years later, only Sir John Simon and Sir Samuel Hoare of the main British participants had written their memoirs, the former having intentionally restricted himself to material already then made public. The Ethiopian affair figured only as an important second-stream event in Taylor's general study, which did not concern itself in detail with the books of Foreign Office officials, such as that of Sir Robert (later Lord) Vansittart, which had appeared in the meantime.