Pope Calixtus II

Pope Calixtus II, born Roberto of Lorraine, was the pope from 1119 to 1124. He is best known for resolving the Investiture Controversy, a major conflict between the church and secular rulers over who had the authority to appoint church officials like bishops. His negotiations led to the Concordat of Worms in 1122, which established a compromise: the church would select bishops, but the emperor had some influence. Calixtus II aimed to strengthen church independence and authority while maintaining peaceful relations with rulers, helping to define the balance of power between church and state in medieval Europe.