Overview
Pope John XI (; 910 – December 935) was the bishop of Rome and nominal ruler of the Papal States from March 931 to his death. The true ruler of Rome at the time was his mother, Marozia, followed by his brother Alberic II. His pontificate occurred during the period known as Saeculum obscurum.
Parentage
John was the son of Marozia, the most powerful woman in Rome and the wife of Alberic I at the time of John's birth. According to hostile chronicler Liutprand of Cremona and the Liber Pontificalis, John's father was not Alberic but Marozia's lover Pope Sergius III. However, neither Auxilius of Naples nor Eugenius Vulgarius, both of whom were exact contemporaries of Sergius, and both of whom were hostile towards Sergius for his attacks on Formosus, mention this allegation at all. The highly reliable chronicler Flodoard also refers to John as the brother of Alberic II, and does not mention the allegation either.
Ferdinand Gregorovius, Ernst Dümmler, Thomas Greenwood, Philip Schaff, and Rudolf Baxmann accept Liutprand's account. Horace Kinder Mann considers this story "highly doubtful", highlighting Liutprand's bias. Reginald L. Poole, Peter Llewelyn, Karl Josef von Hefele, August Friedrich Gfrörer, Ludovico Antonio Muratori, and Francis Patrick Kenrick also maintain that Pope John XI was sired by Alberic I of Spoleto.
Pontificate
Marozia was the de facto ruler of Rome at the time and she used her power and influence to ensure that John, who held the titulus of Santa Maria in Trastevere, was elected to the papacy in March 931. Following the overthrow of Marozia and her husband Hugh of Italy around late 932, John XI fell under the control of his brother Alberic II. After being initially imprisoned, he was confined to the Lateran Palace for the remainder of his pontificate. During this time only authority left to John was the exercise of his purely spiritual duties. All other jurisdiction was exercised through Alberic II. This was not only the case in secular, but also in ecclesiastical affairs.
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