John XII

Pope John XII (Latin: Ioannes XII; c. 930/937 – 14 May 964), born Octavian, was the bishop of Rome and ruler of the Papal States from 16 December 955 to his death in 964. He was related to the counts of Tusculum, a powerful Roman family which had dominated papal politics for over half a century. He became Pope somewhere between the ages of 17 and 25. If he was 17 then he may have been the youngest Pope in history; if not, that title may belong to Benedict IX, who was between the ages of 11 and 20 when elected.

In 960, he clashed with the Lombards to the south. Unable to control Rome easily, he sought help from King Otto I of Germany and crowned him emperor. John XII's pontificate became infamous for the alleged depravity and worldliness with which he conducted his office. He soon fell out with Otto who, in 963, convened a synod in Rome which purported to depose John XII for his crimes and elect Leo VIII as his successor. John XII died several months after the synod declared him to be deposed.

He is almost universally regarded as one of the worst Popes in history.