The Church of Rome started in the mid 1st century. The Church of Jerusalem started on the day of Pentecost. Form there, Christianity spread quickly to all the major cities of the Middle East. The first centers of Christianity were Jerusalem, Antioch, Ephesus, Alexandria, and Rome. For the first 400 years, Rome was Orthodox in every sense. Then, as a result of differences in language, political circumstances, and geography, they began to change. The Bishops of Rome started wanting more and more political power. They were unhappy with being recognized as "first among equals" by Bishops in Jerusalem, Antioch, Alexandria, and Constantinople. Then the Bishops of Rome began to demand that they recognize them as the "supreme Bishop" of the whole Church. The people of Rome would not listen, so Rome was separated creating the Roman Catholic Church. On the chart Russia has the highest population of Eastern Orthodox people. But on the other hand Greece has the highest percentage of their population that is Eastern Orthodox. It would be accurate to say that the Patriarch of Constantinople has great power over Russia, Ukraine and Ethiopia because the majority of the population in these three places is Eastern Orthodox. So this leads them all to listen and to follow the Patriarch of Constantinople. The dangers faced by the Christians in Rome meant that they had to meet in secret. They usually used underground tombs as these were literally out of sight. Rome had a large number of poor people within its population and Christianity continued to grow. In AD 313, the Emperor Constantine made Christianity legal and for the first time, they were allowed to openly worship. Churches were quickly built not just in Rome but throughout the empire. In AD 391, the worship of other gods was made illegal.