Saeculum obscurum (, "the dark age/century"), also known as the Pornocracy or the Rule of the Harlots, was a period in the history of the Papacy during the first two-thirds of the 10th century, following the chaos after the death of Pope Formosus in 896 which saw seven or eight papal elections in as many years. It began with the installation of Pope Sergius III in 904 and lasted for sixty years until the death of Pope John XII in 964. During this period, the popes were influenced strongly by a powerful and allegedly corrupt aristocratic family, the Theophylacti, and their relatives and allies. The era is seen as one of the lowest points of the history of the Papal office. Periodisation The saeculum obscurum was first named and identified as a period of papal immorality by the Italian cardinal and historian Caesar Baronius in his Annales Ecclesiastici in the sixteenth century. Baronius's primary source for his history of this period was a contemporaneous writer, Bishop Liutprand of Cremona. Baronius himself was writing during the Counter-Reformation, a period of heightened sensitivity to clerical corruption. His characterisation of the early 10th-century papacy was perpetuated by Protestant authors. The terms "pornocracy" (, from Greek pornokratiā, "rule of prostitutes"); hetaerocracy ("government of mistresses"); and the Rule of the Harlots () were coined by Protestant German theologians in the nineteenth century. Historian Will Durant refers to the period from 867 to 1049 as the " of the papacy". 10th-century popes The Theophylacti family sprung from Theophylactus. They held positions of increased importance in the Roman nobility, such as iudex ("judge"), vestararius, gloriosissimus dux ("most-glorious duke"), consul, senator, and magister militum. Theophylact's wife Theodora and daughter Marozia held a great influence over the papal selection and religious affairs in Rome through conspiracies, affairs, and marriages. Marozia became the concubine of 45-year-old Pope Sergius III when she was 15 and later took other lovers and husbands. She ensured that her son John (who was rumoured to have been fathered by Sergius III) was seated as Pope John XI according to Antapodosis sive Res per Europam gestae (958–962), by Liutprand of Cremona (c. 920–972). Liutprand affirms that Marozia arranged the murder of her former lover Pope John X (who had originally been nominated for office by Theodora) through her then husband Guy of Tuscany possibly to secure the elevation of her current favourite as Pope Leo VI.