Pope Callistus II Date of birth unknown; died 13 December, 1124. His reign, beginning 1 February, 1119, is signalized by the termination of the Investiture controversy which, begun in the time of Gregory VII, had raged with almost unabated bitterness during the last quarter of the eleventh century and the opening years of the twelfth. … Continue reading December 13 – Elected Pope to Fight the Emperor