Republic of St Peter I

  General Description   The Papal State originated in the Patrimony of St. Peter, which initially included over four hundred estates, many of them in Sicily. These came from donations from wealthy Christians, whose philanthropy accelerated after Emperor Constantine. ^[1] The eighth century popes called their state "The Republic of St. Peter". The popular name "Papal States" was only used from the late middle ages. ^[2]
The Republic of St Peter (711-904 CE) was under nominal Byzantine suzerainty until 781 CE when the capital of the Byzantine exarchate was at Ravenna ^[3] which was connected to Rome by the thin strip of Byzantine territory running across the Appennines and through Perugia. The Pope was elected by citizens and the army - usually based on the choice of the clergy. Representatives would the certify the choice to the Exarch in Ravenna for imperial approval. The Exarch could make the choice himself in case of disagreement. ^[4]
In 781 CE Charlemagne asserted Frankish suzerainty over the region. After this time, the years of the Byzantine Emperor’s reign were no longer used for dating Papal documents or on the minting of imperial coins in the mint of Rome. ^[5] During the ninth century the Papacy was released from Carolingian influence as the Frankish empire began to break up. ^[6]
This also meant that between the end of the ninth century and the 960s, the papacy had no powerful protectors outside Italy. Political power in Rome and Lazio lay in the hands of elite families, such as the Theophylacti and other powerful Roman baronial families. ^[7]
Papal governmental administration was small-scale but effective and organized into departments, with separate heads for the chancery and archives. ^[3] Notaries were career bureaucrats with the primicerius notariorum the head of college of notaries. ^[8] The governance of the wider mountainous region was characterised by small countships and marquisates centered upon a fortified rocca.
The population of the polity is hard to estimate but it is likely the city of Rome lost half its population between 800 CE and 900 CE when it held a mere 40,000 people.

[1]: (Brown 2003, 206) Brown, Peter. 2003. The Rise of Western Christendom. Triumph and Diversity, 200-1000. Oxford: Blackwell Publishing, Inc.

[2]: (Noble 2011, xxi) T F X Noble. 2011. The Republic of St. Peter: The Birth of the Papal State, 680-825, University of Pennsylvania Press.

[3]: (Partner 1972, 9) P Partner. 1972. The Lands of St. Peter: The Papal State in the Middle Ages and the Early Renaissance, University of California Press

[4]: (Trevor, 1869, 113) G Trevor. 1869. Rome and Its Papal Rulers, A History of Eighteen Centuries, The Religious Tract Society, London [1]

[5]: (Grierson and Blackburn 2007, 259)

[6]: (Barraclough 1968, 55) Geoffrey Barraclough. 1968. The Medieval Papacy Norwich: Harcourt, Brace & World, 1968.

[7]: (Stearns 2001 173) P Stearns. 2001. The Encyclopedia of World History. 6th Edition. James Clarke & Co Ltd. Cambridge.

[8]: (Richards 1979, 290-292) J Richards. 1979. The Popes and the Papacy in the Early Middle Ages, 476-752, Routledge & Kegan Paul