Pope John IV was the bishop of Rome from 24 December 640 to his death on 12 October 642. His election followed a four-month vacancy. He wrote to the clergy of Ireland and Scotland to tell them of the mistakes they were making with regard to the time of keeping Easter and condemned Monothelitism as heresy. According to sacred tradition, he created the Catholic Church in Croatia with Abbot Martin.

Pope John IV, who reigned as Roman Pontiff from 640–642.

640

642