Arnold of Brescia, (1090-1155), was a monk from Italy who participated in the Commune of Rome and started the subsequent rebellion.

Arnold's life in France

As a young priest, Arnold studied under the tutelage of famed reformer and poet, Pierre Abélard. He took to Abélard's philosophy of reform ways and became very critical of the Catholic Church when it became involved in a land struggle in Brescia. He called on the Church to renounce ownership of property and return it to the city government so as not to be tainted by possession. The issue came before the Synod of Sens in 1140 and both Arnold and Abélard's positions were overruled by Bernard of Clairvaux. Arnold stood alone against the church's decision after Abélard's capitulation and was then exiled by Pope Innocent II as a consequence. His writings were also burned up to silence his position further.

Arnold's Life and Death in Rome

In 1145, Pope Eugene III then ordered him to submit himself to the mercy of the Church in Rome. When he arrived, he found that the Commune of Rome had taken control of the city away from the Pope and founded a republic. Arnold sided with the people immediately and soon rose to the leadership of this radical new group, calling for liberty and democratic rights. He succeeded in driving Pope Eugene into exile in 1146 for which he was excommunicated. When Pope Eugene returned to the city in 1148, Arnold continued to lead the blossoming republic despite his excommunication. After Eugene's death, Pope Adrian IV swiftly took back control of Rome under a Holy Week interdict in 1155, forcing Arnold again into exile. He was seized by Holy Roman Emperor Frederick I's armies when they arrived in Rome and he was finally tried by the Roman Curia as a rebel. Importantly, he was never accused of heresy. As a result of his conviction for rebellion, he was executed but remained a hero to large sections of the Roman people. Arnold's life was later used by the Reformational authorities and advocates of later Roman communes.