Abstract: The organisation of the Romanian prisoners in Italy in the Legion of Romanian Volunteers gained momentum after the Congress of the Austro-Hungarian Nations held on 8 April 1918, which a Romanian delegation also attended. Professor Simion Mândrescu, president of the Association of Romanians from Transylvania and Banat, remained in Italy to organise the Romanian prisoners in military units that were to fight in the Italian army against the Central Powers. In the spring and summer of 1918, the “Pro Romania” and „Pro Romeni” associations, consisting of Italian MPs, senators, scientists etc., organised events in Rome, Turin, Naples etc. to support the programme of the Committee of the Romanians from Transylvania, Banat and Bucovina that promoted the constitution of the Romanian nation-state.