When Christianity had become the religion of many people, it was necessary for the Church to have some form of organization; and such an organization speedily began to grow. First we find some of the Christians set aside to act as priests, and have charge of the services in the church. We find next among the priests in each city one who comes to be styled the "overseeing priest" or bishop, whose duty it was to look after the affairs of the churches in his district. Gradually, too, the bishops in the more important cities come to have certain powers over the bishops of the smaller cities about them; these were then called "archbishops." And finally, there came to be one out of the many hundred bishops of the Church who was looked up to more than any other person, and whose advice was sought in all important Church questions. This was because he had charge of the church in Rome, the most important city of the Empire, and because he was believed to be the successor of St. Peter, the chief of the Apostles. The name "Pope," which means father, was given to him; and it was his duty to watch over all the affairs of the Church on earth, as a father watches over the affairs of his family.

Of course, all this organization did not spring up at once, ready made. Great things grow slowly; and so it was only slowly that this organization grew. Sometimes disputes arose as to the amount of power the priests should have over the "laymen," as those who were priests were called; and sometimes there were disputes among the "clergy" or churchmen, themselves. Sometimes these disputes were about power, and lands, and things of that sort; for now the Church had become wealthy and powerful, through gifts made to it by rulers and pious laymen. More often the questions to be settled had to do with the belief of the Church,—that is, with the exact meaning of the teachings of Christ and the Apostles, as they are recorded in the Bible and in the writings of the early Christian teachers. Many of the questions which were discussed seem strange to us; but men were very much in earnest about them then. And at times, when a hard question arose concerning the belief of the Church, men would travel hundreds of miles to the great Church Councils or meetings where the matter was to be decided, and undergo hardships and sufferings without number, to see that the question was decided as they thought was right.

One of the questions which caused most trouble was brought forward by an Egyptian priest named Arius. He claimed that Christ the Son was not equal in power and glory to God the Father. Another Egyptian priest named Athanasius thought this was a wrong belief, or "heresy"; so he combated the belief of Arius in every way that he could. Soon the whole Christian world rang with the controversy. To settle the dispute the first great Council of the Church was called by the Emperor Constantine in the year 325 It met at Nicæa, a city in Asia Minor. There "Arianism" was condemned, and the teaching of Athanasius was declared to be the true belief of the Church. But this did not end the struggle. The followers of Arius would not give up, and for a while they were stronger than their opponents. Five times Athanasius was driven from his position of archbishop in Egypt, and for twenty years he was forced to live an exile from his native land But he never faltered, and never ceased to write, preach, and argue for the belief which the Council had declared to be the true one. Even after Arius and Athanasius were both dead, the quarrel still went on. Indeed, it was nearly two hundred years before the last of the "Arians" gave up their view of the matter; but in the end the teachings of Athanasius became the belief of the whole Church.

One consequence of this dispute about Arianism was that the churches in the East and West began to drift apart. The Western churches followed the lead of the bishop of Rome and supported Athanasius in the struggle, while the Eastern churches for a time supported Arius. Even after Arianism had been given up, a quarrel still existed concerning the relation of the Holy Ghost to the Father and Son. As time went on, still other disputes arose between the East and West. The Roman clergy shaved their faces and were not permitted to marry, while the Greek clergy let their beards grow, and married and had children. Moreover Rome and Constantinople could not agree as to whether leavened or unleavened bread should be used in the Lord's Supper. Still less could the great bishop of Constantinople, where the Emperor held his court, admit that the power of the bishop of Rome was above his own. Each side looked with contempt and distrust upon the other; for the one were Greeks and the other Latins, and the differences of race and language made it difficult for them to understand one another.

Gradually the breach grew wider and wider. At last, after many, many years of ill feeling, the two churches broke off all relations. After that there was always a Greek Catholic Church (which exists to this day) as well as a Roman one; and the power of the Pope was acknowledged only by the churches in the Western or Latin half of the world.

The Church, of course, was as much changed by the conquests of the Germans as was the rest of the Roman world. The barbarians who settled in the lands of the Empire had already become Christians, for the most part, before the conquest, but they were still ignorant barbarians. Worst of all, the views which they had been taught at first were those held by the Arians; and this made them more feared and hated by the Roman Christians. Among the citizens of the Empire, as well as among the barbarians, there was also much wickedness, oppression, and unfair dealing. "The world is full of confusion," wrote one holy man. "No one trusts any one; each man is afraid of his neighbor. Many are the fleeces beneath which are concealed innumerable wolves, so that one might live more safely among enemies than among those who appear to be friends."

The result of this was that man began to turn from the world to God. Many went out into the deserts of Egypt, and other waste and solitary places, and became hermits. There they lived, clothed in rags or the skins of wild beasts, and eating the coarsest food, in order that they might escape from the temptations of the world. The more they punished their bodies, the more they thought it helped their souls; so all sorts of strange deeds were performed by them. Perhaps the strangest case of all was that of a man named Simeon, who was called "Stylites," from the way in which he lived. For thirty years,—day and night, summer and winter,—he dwelt on the top of a high pillar, so narrow that there was barely room for him to lie down. There for hours at a time he would stand praying, with his arms stretched out in the form of a cross; or else he would pass hours bowing his wasted body rapidly from his forehead to his feet, until at times the people who stood by counted a thousand bows without a single stop.

Such things as these happened more frequently in the Eastern than they did in the Western Church. In the West, men were more practical, and when they wished to flee from the world, they went into waste places and founded "monasteries," where the "monks," as they were called, dwelt together under the rule of an abbot. In the West, too, the power of the bishop of Rome became much greater than that possessed in the East by the bishop of Constantinople. It was because the Pope was already the leading man in Rome that Leo went out to meet the Huns and the Vandals, and tried to save Rome from them. About one hundred and forty years later, Pope Gregory the Great occupied even a higher position. He not only had charge of the churches near Rome, and was looked up to by the churches of Gaul, Spain and Africa more than Leo had been; but he also ruled the land about Rome much as an emperor or king ruled his kingdom.

Gregory was born of a noble and wealthy Roman family. When he inherited his fortune he gave it all to found seven monasteries, and he himself became a monk in one of these. There he lived a severe and studious life. At length, against his own wishes, he was chosen by the clergy and people to be Pope. This was in the very midst of the Dark Ages. The Lombards had just come into Italy, and everything was in confusion. Everywhere cities were ruined, churches burned, and monasteries destroyed. Farms were laid waste and left uncultivated; and wild beasts roamed over the deserted fields. For twenty-seven years, Gregory wrote, Rome had been in terror of the sword of the Lombards. "What is happening in other countries," he said, "we know not; but in this the end of the world seems not only to be approaching, but to have actually begun." The rulers that the Eastern Emperors set up in Italy, after it had been recovered from the East-Goths, either could not or would not help. And to make matters worse, famine and sickness came, and the people died by hundreds.

So Gregory was obliged to act not only as the bishop of Rome, but as its ruler also. He caused processions to march about the city, and prayers to be said, to stop the sickness. He caused grain to be brought and given to the people, so that they might no longer die of famine. He also defended the city against the Lombards, until a peace could be made. In this way a beginning was made of the rule of the Pope over Rome, which did not come to an end until the year 1871.

Gregory was not only bishop of Rome, and ruler of the city. He was also the head of the whole Western Church, and was constantly busy with its affairs.

Before he was chosen Pope, Gregory was passing through the market-place at Rome, one day, and came to the spot where slaves—white slaves—were sold. There he saw some beautiful, fair-haired boys.

"From what country do these boys come?" he asked.

"From the island of Britain," was the answer.

"Are they Christians?"

"No," he was told; "they are still pagans."

"Alas!" exclaimed Gregory, "that the Prince of Darkness should have power over forms of such loveliness."

Then he asked of what nation they were.

"They are Angles," replied their owner.

"Truly," said Gregory, "they seem like angels, not Angles. From what province of Britain are they?"

"From Deira," said the man naming a kingdom in the northern part of the island.

"Then," said Gregory, making a pun in the Latin, "they must be rescued de ira  [from the wrath of God]. And what is the name of their king?"

"Ælla," was the answer.

"Yea," said Gregory, as he turned to go, "Alleluia must be sung in the land of Ælla."

At first Gregory planned to go himself as missionary to convert the Angles and Saxons. In this he was disappointed; but when he became Pope he sent a monk named Augustine as leader of a band of missionaries. By their preaching, Christianity was introduced into the English kingdoms, and the English were gradually won from the old German worship of Woden and Thor.

Gregory also had an important part in winning the West-Goths and Lombards from Arianism to the true faith. In all that he did Gregory's action seemed so wise and good that men said he was counselled by the Holy Spirit; and in the pictures of him the Holy Spirit is always represented, in the form of a dove, hovering about his head.

Gregory has been called the real father of the Papacy of the Middle Ages. This is no small praise, for the Papacy, in those dark ages, was of great service to Christendom. In later ages, popes sometimes became corrupt; and at last the Reformation came, in which many nations of the West threw off their obedience. But in the dark days of the Middle Ages, all the Western nations looked up to the Pope as the head of the Church on earth, and the influence of the popes was for good. There was very little order, union, and love for right and justice in the Middle Ages, as it was; but no one can imagine how much greater would have been the confusion, the lawlessness, and the disorder without the restraining influence of the Papacy.