The Sarajevo Assassination of June 28 took Austria-Hungary into World War I, and meant the effective end of the party, which had had no meaningful activity after establishing itself.Cocuz, p. 450; Diacon, pp. 163–164 Nominally, however, the Peasantist group continued to be represented in the House until late 1918, through Onciul and Simionovici.Bălan, pp. 82, 84 From the early stages of war, Onciul was more radical than the Concordia elites in supporting the Austrian cause, adopting the imperial slogan A.E.I.O.U..Bălan, pp. 14, 15 This issue took the forefront in July 1914, at the Schoolteachers' Congress in Suczawa. Onciul and Chisanovici tried to prevent it from taking place, claiming that it would be used for promoting irredentism.Iuliu Maior, "Pagini științifice. Impresii din Bucovina", in Unirea. Foaie Bisericească-Politică, Nr. 75/1914, p. 5 Onciul then openly accused a guest speaker, Onisifor Ghibu, of "high treason" against Austria."Din Bucovina", in Românul (Arad), Nr. 158/1914, p. 5
