8 dated entries naming Papal Bull, drawn from 8 separate years between 1054 CE and 1503 CE. Nothing here is written by us: each line is the sentence a Wikipedia year article used, and the link beside it opens the exact revision.
1054July 16 – East-West Schism: Humbert of Silva Candida, representative of the newly deceased Leo IX, breaks the relations between Western and Eastern Churches, through the act of placing an invalidly-issued Papal Bull of excommunication during the celebration of the Divine Liturgy.source
12th century
1155A plan to conquer Ireland is approved by Adrian IV in a Papal bull (a formal proclamation issued by the pope) called Laudabiliter. It gives Henry II lordship over Ireland, but the Irish kings resist English rule.source
13th century
1216December 22 – Honorius III officially approves the Order of Preachers (the Dominican Order), by the Papal bull Religiosam vitam.source
14th century
1347January 26 – Charles University in Prague is founded by a bull issued by Pope Clement VI, at the request of Charles I, King of Bohemia.source
15th century
1451January 7 – Pope Nicholas V issues a Papal Bull to establish The University of Glasgow; classes are initially held in Glasgow Cathedral.source
1482March 22 – Pope Sixtus IV, in a special bull, grants self-government rights to the Italian town of Ascoli Piceno.source
1484December 5 – Pope Innocent VIII issues the Papal bull Summis desiderantes affectibus, giving the Inquisition a mission to hunt heretics and witches in Germany, led by Heinrich Kramer and Jacob Sprenger.source
16th century
1503May 28 – James IV of Scotland and Margaret Tudor of England are married as per the Treaty of Perpetual Peace by Pope Alexander VI, according to Papal bull.source