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Limits RegistryPope Pius IX reigned from June 16, 1846, until his death on February 7, 1878 — nearly 32 years — the longest verified papal reign in the history of the Roman Catholic Church, a period that included the loss of the Papal States and the First Vatican Council.
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Pope Pius IX reigned from June 16, 1846, until his death on February 7, 1878 — nearly 32 years — the longest verified papal reign in the history of the Roman Catholic Church, a period that included the loss of the Papal States and the First Vatican Council.
The longest reign of a Pope of the Roman Catholic Church for which the start and end dates are historically well documented, excluding the traditional reign attributed to Saint Peter, whose exact dates are not historically verifiable.
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Limits Registry. LR-LONGEST-VERIFIED-PAPAL-REIGN. Longest verified reign of a Pope. 2026.