Even though Italy officially joined the IAU in 1921, Italian astronomers were involved in its birth as early as 1919, when Annibale Riccò, Director of the Astrophysical Observatory of Catania, proposed to the IAU Committee to hold its first General Assembly in Rome. This contribution will analyze the role played by Italian astronomers in the development of the IAU from its foundation to the Second World War. The recent project of reordering of the astronomical historical archives in Italy permits for the first time a more in-depth study of the relations between Italian astronomers and the international scientific community.
