Papal ships will be referred as HHFS - His Holy Father's Ship - before ship's name.These abbreviations will distinguish same ship´s name from different nations and government warships from pivateers or privately-owned merchantmen.

The Pontifical Navy (Marina Militare Pontificia) was formed by the John VIII (875-881) and ceased to exist when the main naval base Civitavecchia was incorporated into the Kingdom of Italy in 1870. Untill 1815 the Navy ships were united with the Merchant Navy under supervision of Prefetto di S. Angelo as commisario del mare. In 1798 twelve the most valuable ships were taken by Napoleon to meet their fate at Aboukir on August 1st, 1798. With the return of the Pope Pius VII to Rome on May 26th, 1814 the Navy was reorganized passing under control of the Camerlengo di Santa Romana Chiesa. In 1817 a Custom Service was formed. In 1828 the Presidenza delle Armi was constituted and the navy passed under its control.