The first 33 leaders of the Christian Church (popes) were martyred – Saint Peter to Saint Sylvester. In 313, Emperor Constantine proclaimed a “toleration” of Christianity. In 380, the succeeding Emperor Theodosius made Christianity the “official religion” of the Roman Empire. It was then that the popes became powerful leaders in religious and civil society.
Besides receiving spiritual power from Christ, the popes believed if they could also have temporal power then they could compete more practically with earthly princes for world peace. King Pepin, the ruler of what became known as the Holy Roman Empire, donated the central territories of Italy to the papacy. Pepin’s son, Charlemagne, confirmed the donation in 781. These papal states were governed by the pope as the papa-re (pope-king) between 754 until 1870.