Eusebius of Caesarea, also known as Eusebius of Pamphili—but not to be confused with his contemporary, Eusebius of Nicomedia—was a fourth century Christian scholar, known as “the Father of Church History.”

Despite the nickname, Eusebius was not a Church Father. And while he was an influential bishop, he was not a saint—in fact, he was excommunicated from the church for heresy.

Still, Eusebius’ writings hold an important place in Christianity. His careful attention to detail and thorough treatment of his subjects provide an invaluable lens for us to examine the early church. His most famous work, Ecclesiastical History, also called Church History, chronologically documents Christian history from the time of the apostles to Eusebius’ own lifetime, recording the succession of church leadership and recognition of heresies, among other things. It was an unprecedented undertaking.

Most of what we know about Eusebius comes from hints in his own writings, the works of church historians who came after him, and a smattering of mentions from his contemporaries. His successor, Acacius, wrote a biography called Life of Eusebius, but it didn’t survive.

So what do we know about the “Father of Church History,” and what, if anything, can we learn from him? Can we trust the word of a heretic?

When and where did Eusebius live?

Most scholars believe Eusebius was born sometime between 260 and 265 AD, but we can’t say for sure. Scholars use this range largely because in Ecclesiastical History, Eusebius refers to the third century bishop Dionysius of Alexandria as a contemporary, and Dionysius died in 264 AD.

Scholars generally assume Eusebius was born in the town where he spent most of his life: Caesarea. He was educated and baptized there, and the bishop of Caesarea, Agapius, made him a leader of the local church (a presbyter). Agapius may have trained and baptized Eusebius himself, and Eusebius eventually succeeded him as bishop of Caesarea. This is why we know him as Eusebius of Caesarea.

Is that the same Caesarea from the New Testament?

Yep—Eusebius was from the same Caesarea mentioned throughout Acts and the epistles. Caesarea was a coastal town in what is now modern-day Israel, and it was an influential city in the early Christian church. The third century church father, Origen, and his fourth century follower, Pamphilus, earned Caesarea a reputation as a scholarly Christian community.

Eusebius was influenced by Origen

Pamphilus established a Christian library in Caesarea which included the original manuscripts of Origen’s works. Eusebius received his education under Pamphilus, exposing him to Origen’s writings, as well as the church father’s personal library of important Christian works and influential writings (including the Hexapla, which contained a word-for-word comparison of the Hebrew Bible and the Septuagint).

Scholars believe there were more than 30,000 books in the Library of Caesarea, giving Eusebius access to an immense collection of ancient and contemporary knowledge.

Eusebius drew much of his insights about the early church from Origen, and he developed such a close relationship with his teacher (Pamphilus) that he was known as Eusebius Pamphili, meaning “son of Pamphilus.” Scholars don’t know what this title means. Was he literally Pamphilus’ son? Maybe, but probably not. Most scholars believe that Eusebius was adopted, or else considered Pamphilus’ “spiritual son,” but no one can say for sure.

When did Eusebius die?

We can’t confirm exactly when Eusebius died, but scholars have a lot more to work with to estimate his date of death than they do to determine his date of birth. We know from a council in Antioch that Eusebius’ successor, Acacius, had taken his place as bishop by at least 341. And the fifth century Christian historians Socrates (no, not that Socrates) and Sozomen tell us that he died after Athanasius was banished for the second time, which was in late 339, and before Constantine II died, which was in early 340.

So Eusebius died between the later part of 339 AD and the beginning of 340 AD.

What did Eusebius write?

With complete access to the prestigious Library of Caesarea, Eusebius wrote a biography and numerous works on topics like church history and apologetics. His works are often polemical, challenging other ideas, belief systems, and people, and he carefully cites the works of other writers. Some of his writings only survived in fragments, but many are still fully intact.

Some of his most famous works are Ecclesiastical History, Chronicle, Life of Constantine, On the Martyrs of Palestine, Preparation for the Gospel, and On the Place-Names in the Holy Scriptures.

Ecclesiastical History

Ecclesiastical History was the first complete history of Christianity (well, unless you count the biblical books of LukeActs). Written as a narrative, the ten-volume text began with an introduction on Jesus, then journeyed through apostolic times all the way to the fourth century. Eusebius carefully transmitted the succession of church leaders and recorded the history of influential Christian teachers. He also tells us the history behind various heresies.

Eusebius openly ignores some of the darker aspects of Christianity’s history, and intentionally glosses over some of the internal struggles within the church. Still, this work contains many valuable quotations from original sources found nowhere else.

Preparation for the Gospel

Also well-known by its Latin name, Praeparatio evangelica was Eusebius’ attempt to prove that Christianity was superior to every other religion or philosophy. Since it compares Christianity to other traditions, it quotes heavily from non-Christian writers. Interestingly enough, many of these non-Christian writings are only preserved through this text.

On the Place-Names in Holy Scripture

This unique book is a sort of geological dictionary, listing places mentioned in the Bible and providing contemporary descriptions of their location and geography. Today, it gives historians a helpful look at the geological makeup of fourth-century Palestine and Transjordan, and helps place small ancient villages in relation to well-known cities.

Eusebius described his process this way: “I shall collect the entries from the whole of the divinely inspired Scriptures, and I shall set them out grouped by their initial letters so that one may easily perceive what lies scattered throughout the text.”

You could think of it as an ancient hybrid of an atlas and a Bible dictionary!

What is the value of Eusebius’ writings?

Over the centuries, numerous scholars have called into question Eusebius’ integrity as a historian. His bias for Emperor Constantine is transparent in his eulogy, and he appears to lack discretion when it comes to selecting his sources. But Eusebius also carefully quotes numerous ancient writers, recording exactly where his quotes come from, exposing scholars to the works of other ancient theologians, philosophers, historians, and Church Fathers that would otherwise be lost.

Eusebius and Arianism

Arianism is the heresy that emerged from the teachings of Arius, a third-century priest from Egypt. Arius argued that “if the Father begat the Son, he that was begotten had a beginning of existence: and from this it is evident, that there was a time when the Son was not. It therefore necessarily follows, that he [the Son] had his substance from nothing.”

The heresy was that Jesus was subordinate to God the Father, and that at one point, he didn’t exist. It was one of the primary issues that brought on the First Council of Nicaea, where the church created the Nicene Creed and settled on doctrine about the Trinity, among other things.

Eusebius didn’t subscribe to the heresy himself (though it was only a few steps removed from the theology of Origen), but when it surged into popularity in the fourth century, Eusebius was reluctant to join the church in condemning it. The Nicene Council ruled nearly unanimously against Arianism, declaring that the Father and the Son were equal and that Jesus had been with God from the beginning, and Eusebius signed the agreement.

All of Arius’ writings were burned, and he was banished to the island of Illyria, along with anyone who opposed the Nicene Creed. (And you thought your church had drama.) Eusebius suggested that Arius’ treatment was unnecessarily harsh, and later, when Arianism grew in popularity, Eusebius spoke out against Athanasius (who led the First Council of Nicaea), and helped depose him.

While his own theology didn’t appear to embrace Arianism, he seemed to care more about unity in the church than conformity to doctrine. He openly disputed past decisions of the church and critiqued the leaders who helped Christianity separate itself from the heresy of Arianism. His aversion to division ultimately led to his own excommunication from the church, and drew criticism both from his contemporaries and those who came later.

Can we trust Eusebius?

Eusebius seemed to struggle with letting the church cut its ties with Arianism, but that isn’t the main reason scholars have often called into question his reliability.

He was a close counselor to the Roman Emperor Constantine (and Eusebius wrote a very favorable biography of him), which led later historians to challenge his bias. Using his own words and his use of a Plato quote, some have argued that he admitted to lying for the greater good. Others have accused him of being a sloppy historian. Either way, can we trust him?

Was Eusebius biased?

Most scholars and historians would say yes, Eusebius was too close to Emperor Constantine to provide reliable information about him. In his own book of ecclesiastical history, fifth century Christian historian Socrates criticized that Eusebius “has but slightly treated of matters regarding Arius, being more intent on the rhetorical finish of his composition and the praises of the emperor, than on an accurate statement of facts.”

Did Eusebius lie to prove his point?

In The Decline and Fall of the Roman Empire, eighteenth century historian Edward Gibbon writes:

“The gravest of the ecclesiastical historians, Eusebius himself, indirectly confesses that he has related whatever might redound to the glory, and that he has suppressed all that could tend to the disgrace, of religion. . . . Such an acknowledgement will naturally excite a suspicion that a writer who has so openly violated one of the fundamental laws of history has not paid a very strict regard to the observance of the other; and the suspicion will derive additional credit from the character of Eusebius, which was less tinctured with credulity, and more practised in the arts of courts, than that of almost any of his contemporaries.”

Gibbons is likely referencing Eusebius’ admission that he didn’t include everything in his historical account, choosing to omit some unflattering pieces of church history:

“But it is not our place to describe the sad misfortunes which finally came upon them, as we do not think it proper, moreover, to record their divisions and unnatural conduct to each other before the persecution. Wherefore we have decided to relate nothing concerning them except the things in which we can vindicate the Divine judgment.”

Gibbons was criticized for stretching Eusebius’ words to imply something more sinister, but he doubled down on his criticism of Eusebius’ historical reliability in Vindication, citing a chapter heading from Preparation for the Gospel in which Eusebius quotes Plato:

“How it may be lawful and fitting to use falsehood as a medicine, and for the benefit of those who want to be deceived.”

In context, this quote of a quote appears to suggest that Eusebius believed the Old Testament contained lies, and that it was OK as long as it served the greater good of pointing people to God. However, the Greek word translated “falsehood” here (pseudos) appears to have a range of meaning, including “fiction,” and while the word can simply mean “lie,” some nuances are far less malicious than the English translation.

Some have argued that Eusebius’ use of this Plato quote is simply a continuation of the theology of Origen, who wrote this about Scripture: “all has a spiritual meaning, but not everything has a literal meaning” (De Principiis).

It’s a bit of a stretch to imply that this quote means Eusebius himself was willing to lie to prove a point he believed in, since it’s in a section heading about the Old Testament, but however he meant to use the Plato quote here, history proves it was a poor choice of words.

But that’s not the only criticism of Eusebius’ reliability, either.

Was Eusebius a bad historian?

For the most part, Eusebius does a good job telling us where he got his information, and he generally uses sources that earlier writers trusted. Unfortunately, he doesn’t always do a good job distinguishing between good sources and bad sources.

He probably wouldn’t share that hoax you saw on Facebook . . . unless someone he trusted did it first. And he might not know that The Onion is satire.

That’s why nineteenth century bishop Joseph Barber Lightfoot argued that Eusebius’ greatest flaw is his seemingly blind acceptance of all source materials:

“A far more serious drawback to his value as a historian is the loose and uncritical spirit in which he sometimes deals with his materials. This shows itself in diverse ways. He is not always to be trusted in his discrimination of genuine and spurious documents.”

But he had to be at least a little discerning, because he clearly rejected writings that were falsely attributed to Clement of Rome. Thankfully, for the most part, Eusebius meticulously tells us where his information comes from, so more critical historians can still try to vett his sources.

An influential Christian writer

Eusebius set out to do something no one before him had ever done. There was no official list of people or writings for him to consult, and yet he managed to piecemeal together an excruciatingly detailed chronological history of the church.

It was an ambitious project, and he didn’t feel up to the task.

In the introduction to Ecclesiastical History, Eusebius wrote, “I feel inadequate to do it justice as the first to venture on such an undertaking, a traveler on a lonely and untrodden path. But I pray that God may guide me and the power of the Lord assist me, for I have not found even the footprints of any predecessors on this path, only traces in which some have left various accounts of the times in which they lived.”

Yet his access to the Library of Caesarea and his education under Pamphilus allowed him to blaze the trail in church history and produce monumental works of ancient scholarship. His writings provided a model for how the church would pass on its legacy to future believers.

For most modern scholars, Eusebius remains an invaluable source of information about the early church and other ancient writers—they just need to avoid the potholes of bias and occasional lack of judgment along the path he left behind.