This work was created by or on behalf of either the government, the former national Fascist Party, an academy, or a non-profit organisation of Italy. It was published prior to 1976, and has no known US copyright registration associated with it. It is now in the public domain in Italy and the United States and possibly elsewhere because its copyright term has expired. According to Law for the Protection of Copyright and Neighbouring Rights n.633, 22 April 1941, revised by the law of 6 February 2016, copyright in works created and published under the name and at the expense of national, provincial and communal governments shall belong to the relevant administration; the same right shall also belong to private legal entities of a non-profit-making character, as well as to the academies and other public cultural organisations (Art. 11). The duration of the rights belonging to the government, the former national Fascist Party, academies and non-profit or public cultural organisations shall be twenty years from first publication, whatever the form in which publication was affected (Art. 29).

This image (or other media file) is in the public domain because its copyright has expired and its author is anonymous.
This applies to the European Union and those countries with a copyright term of 70 years after the work was made available to the public and the author never disclosed their identity.
Important: Always mention where the image comes from, as far as possible, and make sure the author never claimed authorship.