The second pope who was acclaimed an African, Militiades was most likely of Berber parentage. Whether he was born in Africa or in Rome is not known. It is estimated that he was born in the mid 200s.
Militiades, a priest, was elected to the See of Peter after it had been empty for over a year, due to the forced emigration of Pope St. Eusebius to the island of Sicily in 309. Emperor Maxentius had barred him from mainland Italy due to Eusebius' inability to control the violence which was tearing the Church apart at the end of the persecutions. In Italy, those against the lapsi were called Novationists. In North Africa, the poor peasants, especially the Berbers, were referred to as Donatists.
These arguments came up because of the multitude of Christians who were so afraid during the persecutions that some of them sacrificed to the Roman gods, turned over copies of Sacred scriptures or signed letters of intent to sacrifice in order to be safe. Those who suffered or lost loved ones were not willing to forgive and forget. The Novationists felt that only God, at the Last Judgement, could forgive. The Roman Church taught that severe penance would allow the penitents back. The Donatists felt that the whole Roman Church was not valid, neither its teachings nor its sacraments, and any bishop consecrated by a traitor was no bishop.
So, in 311 AD, not only Italy, but North Africa, also, was in deep division. It did not subside when Galerius signed the Edict of Toleration in May, 311. Militiades may have been elected that July because he was a Berber, like many of the Donatists, and could reason more successfully with them.
The first responsibility of the new bishop was to accept back from the government all the churches, cemeteries and other buildings which had been confiscated in the 303 persecutory edict. He assigned two deacons, Strato and Cassianus to coordinate the recovery of and, probably, repair of these items. another early act was to rescue the body of Pope Eusebius and have him buried, with honors, at the Cemetery of Callixtus.
Barely one year later, October 28, 312, was the famous Battle of Milvian Bridge, over the Tiber River in northern Rome. Constantine fought against his co-emperor, Maxentius, and won. Meanwhile Maxentius drowned that day. Constantine insisted afterwards that he had seen a vision indicating that the sign of the Christian God would help him conquer. After that time, he became more and more convinced of the Christian faith.
In keeping with his newfound admiration for the Christian faith, Constantine did two things. In February of 313, Constantine and Licinius issued what is referred to as the Edict of Milan, not only legalizing Christianity, but also requiring Romans to return to Christians all which they had taken, without asking for recompense. He also gave the Church the Lateran Palace, which he had received as part of the dowry from his second wife, Fausta. This became the center of ecclesiastical government and the home of the pope for hundreds of years. thus, Pope Militiades was the first pope to have an official home.
That same year, Constantine asked Militiades to deal with the Donatists, who had already asked the emperor for judges from Gaul to come to Africa and deal with an argument of consecration. In October, 313, Militiades convened a council of 18 bishops from Italy and Gaul to listen to arguments from both sides. In three days they had their conclusion: the orthodox bishop, Caecillian, was considered the rightful bishop over Donatus, usurper bishop of Carthage. The pope thought that was the end of the argument. The Donatists thought not. This marks the first time a Roman emperor sought the use of a pope to improved social order by resolving internal Church problems.
Unfortunately, the Donatists were not easily persuaded. They remained belligerant and the emperor called for another council, this one at Arles, to reconsider the question. This was the first representative council of Christian bishops in Western Europe. However, Militiades died before it was convened.
Militiades helping Constantine marked the first time the Church wove itself into politics. This time it was not as a victim, but as a participant, thus changing the entire presentation of the Church's teaching on spirituality and morals from the individual to the greater community.