Gerardo Bianchi (1220/1225 – March 1, 1302) was an Italian churchman and papal diplomat, an important figure of the War of the Sicilian Vespers.
He was born in Gainago, in the diocese of Parma, studied law at the University of Bologna, and became canon of the cathedral chapter of Parma.
He began his career in the Roman Curia as a Chaplain of Pope Innocent IV (1243-1254) and scriptor in the chancellery (attested in 1245). He is attested as litterarum apostolicarum contradictorum Auditor (Auditor of the Rota) on April 30, 1277. At the time of his elevation to the Cardinalate he was a Protonotarius apostolicus.
Pope Nicholas III in the Consistory of March 12, 1278, created nine cardinals, among them Gerardo Bianchi, whom he named Cardinal Priest of SS. XII Apostoli. On July 15, 1278 Pope Nicholas notified King Philip III of France that he was sending Cardinal Gerardo to Toulouse, where he would join with Cardinal Hieronymus Masci, O.Min. and Master General John of Vercelli, OP, in bringing about a peace with King Alfonso of Castile. On August 5 he was granted the right to employ the services of the members of whatever religious order he wished in his Legation to France. On November 29, the Pope revised his instructions to the three Legates, in accordance with the wishes of the two kings, so that they would hold their meetings in Gascony. On June 9, 1279, Pope Nicholas threatened King Alfonso with severe penalties for not cooperating with the peace process.
Pope Nicholas III (Orsini) died on August 22, 1280, and Cardinal Bianchi participated in the Conclave which was held in Viterbo, beginning in September, 1280. Nicholas III was succeeded by the French cardinal Simon de Brion on February 22, 1281, who took the name Martin IV.
On April 12, 1281, Holy Saturday, Pope Martin IV held a Consistory in which he created seven new cardinals, and promoted Cardinal Gerardo to the Order of Cardinal Bishops and assigned him the suburbicarian see of Sabina.
The Sicilian Vespers, a revolt against the domination of the Island by King Charles of Anjou, which broke out in Palermo at Easter of 1282, shook the island of Sicily. Thousands of Angevins and other French residents of the island were massacred. The cities which had expelled the foreigners sent representatives to Pope Martin, begging him to take them under his protection and recognize them as free cities directly under the sovereignty of the Church. The Pope, always a supporter of King Charles, who had forced his election upon the College of Cardinals, refused. The cities then turned to King Pedro of Aragon for help.