Antipope Guibert

Clement III
Antipope Clement III. (middle) with Henry IV. (left), image froms Codex Jenesis Bose q.6 (1157)
Papacy began	25 June 1080
Papacy ended	8 September 1100
Predecessor	Honorius II (As Antipope) Gregory VII (As Pope)
Successor	Theodoric (As Antipope) Paschal II (As Pope)
Opposed to	Gregory VII, Victor III, Urban II, Paschal II
Personal details
Birth name	Wibert of Ravenna
Born	1029
Died	8 September 1100

Guibert or Wibert of Ravenna (c. 1029 – 8 September 1100) was an Italian prelate, archbishop of Ravenna, who was elected pope in 1080 in opposition to Pope Gregory VII. Gregory was the leader of the movement in the church which opposed the traditional claim of European monarchs to control ecclesiastical appointments, and this was opposed by supporters of monarchical rights led by the Holy Roman Emperor. This led to the conflict known as the Investiture Controversy. Gregory was felt by many to have gone too far when he excommunicated the Holy Roman Emperor Henry IV and supported a rival claimant as emperor, and in 1080 the pro-imperial Synod of Brixen pronounced that Gregory was deposed and replaced as pope by Guibert.

Consecrated as Pope Clement III in Rome in March 1084, he commanded a significant following in Rome and elsewhere, especially during the first half of his pontificate, and reigned in opposition to four successive popes in the anti-imperial line: Gregory VII, Victor III, Urban II, and Paschal II. After his death and burial at Civita Castellana in 1100 he was celebrated locally as a miracle-working saint, but Paschal II and the anti-imperial party soon subjected him to a thorough deletio and damnatio memoriae, which included the exhuming and dumping of his remains in the Tiber. He is considered an anti-pope by the Roman Catholic Church.

He was born into the noble family of the Correggio, probably between 1020 and 1030. He had family connections to the Margraves of Canossa. A cleric, he was appointed to the Imperial chancellorship for Italy by the Empress Agnes in 1058, which position he held until 1063. In 1058 he participated in the election of Pope Nicholas II but on his death in 1061, he sided with the philo-imperial party to elect Cadalous of Parma as Antipope Honorius II against Pope Alexander II. However, owing to the campaigns of Godfrey III, Duke of Lower Lorraine, Archbishop Anno of Cologne, and St. Peter Damian, the Church by-and-large rejected Honorius II and acknowledged Alexander II; probably as a result of these activities, the Empress Agnes dismissed Guibert from the Imperial Chancellorship of Italy.