Papal selection prior to 1059

There was no fixed process for papal selection before 1059. Popes, the bishops of Rome and the leaders of the Catholic Church, were often appointed by their predecessors or secular rulers. While the process was often characterized by some capacity of election, an election with the meaningful participation of the laity was the exception to the rule, especially as the popes' claims to temporal power solidified into the Papal States. The practice of papal appointment during this period would later give rise to the jus exclusivae, a veto right exercised by Catholic monarchies into the twentieth century.

The lack of an institutionalized process for papal succession was prone to religious schism, and many papal claimants before 1059 are currently regarded by the Church as antipopes, although most are not. Furthermore, the frequent requirement of secular approval of elected popes significantly lengthened periods of sede vacante and weakened the papacy. In 1059, Pope Nicholas II succeeded in limiting future papal electors to the cardinals with In Nomine Domini, creating standardized papal elections that would eventually evolve into the papal conclave.

There is no scholarly consensus on when and on what terms Saint Peter arrived in Rome, but most agree that he died there in 64 or 67. Moreover, Peter was never contemporaneously referred to as a "pope" or even a "bishop". Unlike the selection process for a deacon, which is outlined in Acts 6:1-6, there is no biblical method for the selection of a bishop other than by simple apostolic appointment; the earliest text mentioning the election of a bishop is Teaching of the Twelve Apostles circa 100 AD.

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