Pope John IV: The Dalmatian Pope Who Ransomed Captives and Fought Heresy

Pope John IV never crowned an emperor, launched a crusade, or ruled long enough to become one of the famous names of the medieval Papacy.

Yet during his brief pontificate, John confronted one of the most divisive theological controversies of the seventh century, challenged an imperial attempt to impose religious unity, defended the reputation of one of his predecessors, and sent money across the Adriatic Sea to ransom prisoners captured during the destruction of his native Dalmatia (modern Croatia).

John IV’s papacy offers a glimpse into a very different medieval Rome. The Western Roman Empire was long gone, but the popes were still technically subjects of the Byzantine emperor in Constantinople. Slavic migrations were transforming the Balkans, Byzantine territory in Italy was shrinking, and theological disputes could become matters of imperial policy.

Into that world stepped a Dalmatian archdeacon who would spend his short reign trying to protect both the Church and the people of the land where he had been born.

Early Life

John was born in Dalmatia, the Roman province along the eastern coast of the Adriatic Sea. Later tradition and modern scholarship have associated his origins with Iadera, modern Zadar in Croatia.

John’s father, Venantius, held the title of scholasticus, a term generally associated with a legal or administrative official. John appears to have come from an educated family with connections to the imperial and ecclesiastical bureaucracy.

By the time Pope Severinus died in 640, John had risen to become archdeacon of the Roman Church, placing him among the senior clergy responsible for papal administration.

In the seventh century, the pope wasn’t the independent ruler later medieval popes would become. Rome remained part of the Byzantine Empire, and the election of a new pope normally required imperial confirmation before consecration.

John was elected after the death of Severinus and consecrated on 24 December 640.

He inherited a Church already locked in a dangerous argument with Constantinople.

The Monothelite Controversy

The great theological crisis facing John IV concerned a doctrine known as Monothelitism.

The argument grew out of centuries of debate over the nature of Christ.

The Council of Chalcedon in 451 had declared that Christ possessed two natures, divine and human, united in one person. But the definition failed to end the controversy.

Large Christian communities, particularly in Egypt and Syria, rejected Chalcedon, creating religious divisions that also threatened the political unity of the Byzantine Empire.

Emperor Heraclius attempted to find a compromise.

If Christians could agree that Christ possessed two natures but only one will, perhaps the opposing sides could be reunited.

The resulting doctrine became known as Monothelitism.

To seventh-century Christians, the issue touched the very nature of salvation.

If Christ was fully human as well as fully divine, opponents argued, then he must possess a genuinely human will. Removing that human will threatened to make his humanity incomplete.

In 638, Emperor Heraclius issued a document known as the Ecthesis, which supported the doctrine of one will in Christ.

The emperor was attempting to create unity. Instead, he created a religious crisis.

John IV Defies the Imperial Theology

John wasted little time taking a position.

Soon after becoming pope, John IV assembled a synod in Rome that rejected the Ecthesis and condemned Monothelitism.

This was significant because the Ecthesis wasn’t just a theological opinion circulating among bishops. It had been issued under imperial authority.

John was effectively telling Constantinople that the emperor could not settle Christian doctrine by publishing an edict.

The confrontation reflected a larger change slowly taking place in medieval Europe.

For centuries, Roman emperors had summoned councils, intervened in theological disputes, removed bishops, and played an enormous role in Church government. The popes themselves still depended heavily on imperial protection.

Yet Rome was increasingly willing to resist Constantinople when the pope believed imperial policy threatened orthodox teaching.

Heraclius backed away from the controversy shortly before his death in February 641. He disowned responsibility for the Ecthesis and blamed Patriarch Sergius of Constantinople for the document.

But John now faced another uncomfortable problem.

One of the figures being used to defend Monothelitism was a former pope.

Pope Honorius I.

Defending Pope Honorius

Pope Honorius I had corresponded with Patriarch Sergius during the early stages of the controversy.

In those letters, Honorius had used language referring to “one will” in Christ. Supporters of Monothelitism naturally seized upon the words.

If a bishop of Rome had already supported the idea, how could Rome now condemn it? John IV attempted to rescue his predecessor’s reputation.

Writing to the new emperor Constantine III, John argued that Honorius had been misunderstood.

According to John, Honorius had not meant that Christ lacked a human will. Instead, he had meant that Christ did not possess the conflicting and sinful impulses found in fallen humanity. The divine and human wills were not fighting against one another within Christ.

It was an important distinction, and John was not alone in making the argument. Maximus the Confessor would later offer a similar defense.

But the controversy did not disappear.

Nearly forty years after John’s death, the Third Council of Constantinople in 680–681 formally condemned Monothelitism and also condemned Honorius for his role in the controversy.

A Pope Looks Home to Dalmatia

While theologians argued about the nature of Christ, John faced a crisis that was far more immediate and personal. His homeland was being devastated.

During the sixth and seventh centuries, Avar and Slavic groups pushed into the Balkans as Byzantine control weakened. Cities were attacked or abandoned, communities disappeared, and populations were displaced throughout Dalmatia and Istria.

John had left Dalmatia and risen to the highest office in the Western Church, but he had not forgotten where he came from. He sent an abbot named Martin across the Adriatic with large sums of money.

His mission was simple: find Christian captives and buy their freedom.

It is one of the most remarkable episodes of John’s short pontificate.

The papacy possessed no great army capable of restoring Byzantine control over the Balkans. John could not drive invading forces from Dalmatia.

But he could ransom people who had been taken prisoner.

Martin traveled through Dalmatia and Istria using papal funds to rescue captives and assist Christian communities devastated by the invasions.

Saving the Saints of Dalmatia

John’s mission to Dalmatia had another purpose.

Many churches in the region had been damaged or destroyed. With no immediate prospect of rebuilding them, Martin gathered relics associated with important Dalmatian and Istrian martyrs and carried them back to Rome.

John ordered the construction of an oratory beside the Lateran Baptistery to house them. The Oratory of St. Venantius became a permanent memorial to the Christian communities of his homeland.

Among the figures depicted in the mosaics are Dalmatian saints whose relics had been brought to Rome. John IV himself also appears in the decoration, holding a model of the oratory he founded.

More than thirteen centuries later, the mosaic remains a physical connection to a pope whose reign otherwise survives mostly through letters, theological disputes, and brief entries in medieval chronicles.

John could not save the Roman world of Dalmatia as he had known it, so he preserved part of its memory in Rome.

Rome’s Reach Beyond the Mediterranean

John’s short pontificate also shows how far the influence of Rome was beginning to extend.

While still pope-elect, John and other leading Roman church officials wrote to clergy in northern Ireland concerning disagreements over the calculation of Easter.

Different Christian communities continued to use different methods for determining the date of the feast, creating a dispute that would trouble the churches of Britain and Ireland throughout the seventh century.

The letter also warned against the lingering influence of Pelagianism.

Even while dealing with Byzantine emperors and invasions in the Balkans, Rome was communicating with Christians living on Europe’s distant Atlantic fringe.

The medieval papacy was slowly becoming an institution whose concerns stretched far beyond Italy.

Papal Highlights

During his brief reign, Pope John IV:

• ■ Condemned the Ecthesis and opposed the imperial doctrine of Monothelitism.
• ■ Defended Pope Honorius I against accusations that he had taught Monothelitism.
• ■ Sent Abbot Martin to Dalmatia and Istria with papal funds to ransom Christian captives.
• ■ Preserved relics from churches threatened or destroyed during the upheavals in Dalmatia.
• ■ Founded the Oratory of St. Venantius at the Lateran, whose seventh-century mosaics still survive.
• ■ Corresponded with clergy in northern Ireland over the dating of Easter and the danger of Pelagian teaching.

Death and Legacy

Pope John IV died on 12 October 642 after a pontificate of less than two years. He was buried at St. Peter’s Basilica.

His successor, Theodore I, inherited the Monothelite controversy and continued Rome’s opposition to the theology promoted from Constantinople.

John IV did not possess the towering theological reputation of Leo I or Gregory the Great. He did not confront emperors with the political force later displayed by Gregory VII or Innocent III.

His papacy belonged to an earlier and more uncertain world, when Rome remained inside the Byzantine political system and the future shape of medieval Europe was still emerging.

Yet his reign reveals several developments that would become increasingly important.

He asserted that an emperor could not dictate theology to the Church. He demonstrated that papal authority could extend from Ireland to the Balkans.

And when war devastated his homeland, he used the resources of the papacy for action, not simply declarations, ransoming prisoners and preserving what remained of threatened Christian communities.

Perhaps the most fitting monument to John IV is still standing beside the Lateran Baptistery.

There, among golden mosaics and the saints of Dalmatia, the pope is depicted holding the church he created for them.

John IV could not restore the world the invasions had destroyed.

But he made certain that part of it would not be forgotten.

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