The Apostolic Camera (Latin: [Reverenda] Camera Apostolica), formerly known as the Papal Treasury, is an office in the Roman Curia. It was the central board of finance in the Papal administrative system and at one time was of great importance in the government of the States of the Church, and in the administration of justice, led by the Camerlengo of the Holy Roman Church.
Since the middle of the 12th century the Papal chamberlain (camerarius domini papae) was a regular member of the Curia, entrusted with the financial management of the papal court. At that early period the income of the papal treasury came chiefly from many kinds of census, dues, and tributes paid in from the territory subject to the Pope, and from churches and monasteries immediately dependent on him. Cencius Camerarius (later Pope Honorius III, 1216-27) made in 1192 a new inventory of all these sources of papal revenue, known as the Liber Censuum. The previous list dated back to Gelasius I (492-496) and Gregory I (590-604), and was based on lists of the incomes accruing from the patrimonies, or landed property of the Roman Church.
In the 13th century the Apostolic Camera entered on a new phase of development. The collection of the crusade taxes, regularly assessed after the time of Innocent III (1198-1216), imposed new duties on the papal treasury, to which were committed both the collection and distribution of these assessments. Moreover, during the course of this century the system of payment in kind was transformed into the monetary system, a process considerably influenced by the administration of the papal finances. The servitia communia of bishops and abbots (see Annates) were regulated at fixed sums. The income regularly yielded by them to the Curia is by no means small. To these were to be added the annates, taken in the narrower sense, especially the great universal reservations made since the time of Clement V and John XXII, the extraordinary subsidies, moreover, levied since the end of the thirteenth century, the census, and other assessments. The duties of the Apostolic Camera were thus constantly enlarged. For the collection of all these moneys it employed henceforth a great number of agents known as collectores.