John XIII (died September 6, 972) served as Pope from October 1st, 965 until his death in 972.

Spent his career in the papal court.

Elected pope on 5 months after the death of Leo VIII, as a compromise candidate, with the agreement of Emperor Otto I. John's behaviour and foreign backing made him disliked in Rome. There was a revolt resulting in his temporary banishment occurring in December 965, John only returning November 966.

After John's restoration he worked with Otto towards ecclesiastical developments, including the creation of the Archbishopric of Magdeburg. He also developed other Archbishoprics in southern Italy, reducing the influence of the Byzantine Empire and Eastern Orthodox Church there.

Christmas 967 John crowned Otto I's son Otto II as coemperor. Otto II was afterwards married to the niece of the Byzantine Emperor John I Tzimisces, as part of the ongoing attempt to reconcile Eastern and Western Churches.

972 Oswald, Archbishop of York visited Rome. He created new Latin archbishoprics in southern Italy, thus reducing the influence of the Eastern Orthodox church, as well as the Byzantine Empire.