mystic member of the Dominican Third Order; since 1970, Doctor of the Church. The youngest of the twenty or more children of a Sienese dyer, Giacomo Benincasa, Catherine from an early age was devoted to a life of prayer and penance, which she led at home in spite of strong parental opposition. She refused to consider marriage, became a Dominican tertiary, and, after years of solitude and preparation, began to mix with other people, first through nursing the sick in hospital and then by gathering a group of disciples, men and women, including Dominicans, Augustinians, and an English Austin Friar, William Flete. These accompanied her in her frequent journeys; their influence was manifested in some spectacular conversions and in their call to reform and repentance through a renewal of total love of God. Catherine tried to express her ideals in her Dialogue and in her 383 letters, all of which were dictated by her, as she never learnt to write. Her personal holiness, enhanced rather than diminished by frequent and strong criticism, was centred on Christ crucified, seen as the supreme sign of God's love for man.
In the last five years of her life she became involved with the politics of both State and Church. The importance of these interventions has sometimes been exaggerated. Her attempts to make peace between Florence and the papacy (then in Avignon) were disclaimed by the Florentines, while the papacy imposed harsh terms on them for their revolt. Later she added her voice to the many who urged Gregory XI to return to Rome from Avignon and end the so-called Babylonish Captivity with its excessive French influence in the Curia. In 1376, on the same day that Gregory left Avignon by water for Rome, Catherine and her followers began the same journey by road. The two parties met in Genoa, but Catherine then went to Florence, still rent by factions and violence.
In 1378, after the death of Gregory XI, occurred the Great Schism, when Urban VI was elected pope in Rome and a rival set up in Avignon. Catherine wrote frequent letters both to Urban to moderate his harshness and to various European rulers and cardinals urging them to recognize him as the genuine pope. In spite of her reproofs Urban invited her to Rome, where she soon wore herself out working for his cause. She suffered a stroke on 21 April 1380 and died eight days later.
Her friend and biographer, Raymond of Capua, later Master General of the Dominican Order, wrote her Life, which was influential in leading to her canonization in 1461 by the Sienese Pope Pius II.
Exterior accounts of her life are insufficient unless they also emphasize that she was an ardent mystic, totally committed to Christ whom she saw in the Church, in the poor, and the sick as well as in his theandric life on earth. Bold and fearless, she experienced through the fire of love the Divine Mysteries of the Trinity, the Incarnation, and the Church. Exactly because she was so committed to Christ, the sins and imperfections of his ministers caused her acute pain and distress. Sometimes, like St Bernard, her prophetic vision and personal intransigence led her to identify God's cause with her own. In every age of the Church the prophetic witness is needed: she provided it in the 14th century to a supreme degree.