#498 – Anthony Kaldellis: Roman Empire, Byzantine Empire, Rise & Fall of Empires

Episode of Lex Fridman Podcast · June 30, 2026 · 3 h 59 min

Historian Anthony Kaldellis and Lex Fridman trace 2,200 years of Roman history, arguing the Byzantine Empire was simply the Roman Empire and explaining its longevity.

Summary

Lex Fridman spoke with historian Anthony Kaldellis about the full span of Roman history from the founding of Rome to the fall of Constantinople in 1453. Kaldellis argued that the so-called Byzantine Empire was in every legal and cultural sense the Roman Empire, a political community of Roman citizens whose history was continuous, and that the label "Byzantine" reflects later Western European politics. He described a state whose emperors had no right to the throne, roughly 46% of whom were violently overthrown, and who therefore projected a persona of tireless, accountable service, a persona he believes they largely lived up to.

The conversation covered the Edict of Caracalla, which Kaldellis called an explosion of citizenship that genuinely opened power to provincials; the Crisis of the Third Century and Diocletian's bureaucratic and universal tax reforms; Constantine's founding of Constantinople and conversion to Christianity, which Kaldellis attributed to personal belief rather than political calculation; and the fall of the West, which he explained as a vicious cycle of barbarian armies seizing tax-producing provinces. He placed taxation at the heart of the society, rejected the idea of isolated peasants beyond the state's reach, and discussed eunuchs as loyal counterweights to entrenched networks.

Kaldellis assessed Justinian as an evenly mixed figure, criticized Heraclius's record, downplayed maximalist estimates of the Plague of Justinian and the popular significance of Iconoclasm, and described Greek fire and the Arab sieges. He argued that the empire's crises were exogenous shocks while its long periods of recovery reflected internal resilience, dated its point of no return to the early 14th century, and attributed its stability to credible government on behalf of subjects and a unified Roman and Orthodox identity. The episode closed with lessons for the present, including a critique of the gap between rhetoric and action in U.S. foreign policy, and reflections on human nature and hope.

Chapters

0:00
Introduction and sponsors
Fridman introduces Anthony Kaldellis and reads sponsor messages.
8:45
The Byzantine Empire was the Roman Empire
Kaldellis argues that the Eastern Roman Empire called itself Roman and that the Byzantine label was a later political invention.
10:52
2,200 years of Roman history
The two outline the periods from the kings to 1453 and identify the major crises of territorial loss.
20:30
Roman identity across time
Kaldellis discusses what held Roman history together, comparing it to the ship of Theseus and weighing Roman pride against political consensus.
32:55
Imperial persona, rhetoric and civil war
Kaldellis describes the accountable, sleepless imperial persona, the absence of a right to the throne, frequent overthrows, and the Hippodrome as a perpetual referendum.
54:20
Edict of Caracalla
The 212 AD grant of citizenship to free inhabitants and its real consequences for provincial access to power are discussed.
1:04:00
Crisis of the Third Century and Diocletian
Kaldellis explains the third-century chaos, the Illyrian soldier-emperors, the Tetrarchy, and Diocletian's bureaucratic and universal tax reforms.
1:21:23
Constantine and Constantinople
Constantine's rise, the strategic founding of Constantinople as a New Rome, and his ranking as the top emperor are covered.
1:33:46
Christianity in the Roman Empire
Kaldellis argues Rome co-opted Christianity, discusses Constantine's conversion, gradual Christianization, and the interplay of Roman, Christian and Greek identities.
1:59:08
Growth of Constantinople and fall of the West
Kaldellis explains Constantinople's population growth through migration and the vicious cycle that brought down the Western Empire.
2:12:11
Government, taxes and eunuchs
The civilian and military administration, tax exemptions, the role of eunuchs, the myth of isolated peasants, and the concept of a monarchic republic are discussed.
2:37:18
Justinian
Kaldellis weighs Justinian's law code, conquests, the Nika riot, Hagia Sophia, and the Plague of Justinian.
2:54:21
Heraclius, the Persian war and the Arab conquests
The Roman-Persian war, Heraclius's mixed record, the Arab conquests, Greek fire, the siege of Constantinople and Iconoclasm are covered.
3:14:05
Recovery, the 11th-century crisis and resilience
Kaldellis discusses his book Streams of Gold, Rivers of Blood and argues that exogenous shocks, not internal decay, caused the empire's crises.
3:27:53
Decline, fall and why the empire lasted
Kaldellis dates the point of no return to the early 14th century and explains the empire's stability through credible government and shared identity.

Key points

What was said, by whom, with the exact words. Timestamps jump to the moment.

Linked moment · 8:45Skip to 8:45 using a listen link in the info box.
Anthony Kaldellis
Kaldellis argues that the burden of proof lies on those who claim the Byzantine Empire was something other than the Roman Empire, since the sources are clear.
“the burden of proof is on those who would assert that what we've been calling the Byzantine Empire is something other than the Roman Empire”
Listen from 9:21 · Byzantine Empire
Anthony Kaldellis
Kaldellis, citing a lesson from Machiavelli, contends that East Roman emperors were generally sincere and did what their rhetoric promised.
“So my research suggests that the emperors and the authorities were generally sincere in what they said”
Listen from 38:19 · Byzantine Empire
Anthony Kaldellis
Kaldellis says that because about 46% of Constantinople's emperors were violently overthrown, every emperor felt insecure and was incentivized to keep subjects content.
“So that's a huge number, which means that every emperor is vulnerable and insecure, and they know it”
Listen from 44:19 · Byzantine Empire
Anthony Kaldellis
Kaldellis argues the Edict of Caracalla was significant because the Romans genuinely implemented universal citizenship, opening top positions to provincials.
“not only did they extend citizenship to everybody, but they meant it. This is something that had teeth”
Listen from 57:21 · Constitutio Antoniniana
Anthony Kaldellis
Kaldellis identifies taxation as the single most important factor at the heart of the Roman state.
“If you asked me to put my finger on one factor, it would be that”
Listen from 1:16:20 · Taxation in the Byzantine Empire
Anthony Kaldellis
Kaldellis ranks Constantine as the top emperor because his decisions, such as founding Constantinople and converting to Christianity, were world-historically consequential.
“The reason I put Constantine at the top of the list is because the decisions that he made were so consequential, just important”
Listen from 1:32:25 · Constantinople
Anthony Kaldellis
Kaldellis argues that the Roman imperial system co-opted Christianity rather than Christianity triumphing over Rome.
“I would lean more toward the second. In other words, that the religion was co-opted by the imperial system”
Listen from 1:34:57 · Christianity
Anthony Kaldellis
Kaldellis says no convincing political explanation exists for Constantine's conversion, leaving personal belief as the most likely reason.
“I have not yet seen a convincing like political argument for Constantine's decision”
Listen from 1:38:25 · Christianity
Anthony Kaldellis
Kaldellis explains the fall of the West as a vicious cycle in which barbarian armies seized provinces, depriving the state of taxes needed to field armies.
“This created this kind of vicious cycle because then the Roman state lost access to the resources from those provinces, that is the taxes”
Listen from 2:05:06 · Fall of the Western Roman Empire
Anthony Kaldellis
Kaldellis rejects the scholarly notion of isolated rural communities cut off from the state, arguing census, taxes, church and coinage enmeshed everyone.
“These people do not exist, these isolated peasants. This is a myth that one day I'm going to write a chapter about this”
Listen from 2:24:06 · Taxation in the Byzantine Empire
Anthony Kaldellis
Kaldellis argues the Eastern Roman Empire was not a military dictatorship because emperors very rarely used the army to control the population.
“They almost never, very, very, very rarely use the army as an instrument of social control”
Listen from 2:34:47 · Byzantine Empire
Anthony Kaldellis
Kaldellis criticizes Justinian's western conquests for stripping the East of armies, allowing the Persians to destroy Antioch.
“I don't think you get a pass for conquering North Africa by surrendering Syria”
Listen from 2:49:27 · Byzantine Empire
Anthony Kaldellis
Kaldellis rejects estimates that the Plague of Justinian killed half the population, noting that wars, taxation and courts continued without pause.
“And some scholars argue for a kind of maximalist position of 50%. I think that would have brought this society to a halt, just logistically speaking”
Listen from 2:52:00 · Plague of Justinian
Anthony Kaldellis
Kaldellis argues the Iconoclasm controversy was socially overblown, mattering intensely only to a small elite who wrote the surviving sources.
“So in my view, this is one of those controversies that only a few people really, really cared about it”
Listen from 3:12:45 · Byzantine Iconoclasm
Anthony Kaldellis
Kaldellis attributes the 11th-century crisis mainly to simultaneous attacks by Normans, Pechenegs and Seljuk Turks rather than internal moral decay.
“But no state can medieval or ancient can realistically survive. The simultaneous attack of three very different kinds of enemies”
Listen from 3:17:59 · Byzantine Empire
Anthony Kaldellis
Kaldellis argues the empire should be defined by its long internally driven recoveries rather than its brief externally caused crises.
“So I see this as a society whose internal organization primes it to stabilize and embark on steady growth”
Listen from 3:21:52 · Byzantine Empire
Anthony Kaldellis
Kaldellis dates the empire's point of no return to the first half of the 14th century, after the loss of Asia Minor, civil wars, Serbian expansion and the Black Death.
“I would say early 14th century, somewhere between 1300 and 1350. the sources of resilience begin to dry up”
Listen from 3:28:58 · Byzantine Empire
Anthony Kaldellis
Kaldellis notes that apart from Bulgaria, there were no separatist movements among Roman provincials, which he cites as evidence the empire could have lasted far longer absent invasions.
“But for the rest of the 1,200 years, you don't find provincials wanting to leave this system”
Listen from 3:32:44 · Byzantine Empire
Anthony Kaldellis
Kaldellis explains the empire's cohesion by the authorities' effort to persuade subjects they ruled on their behalf, combined with a unified Roman and Orthodox identity.
“First is that an extraordinary effort was made by the authorities to persuade their subjects that they were ruling on their behalf”
Listen from 3:36:23 · Byzantine Empire
Anthony Kaldellis
Kaldellis draws the lesson that ruling elites benefit from investing in long-lasting institutions that serve the majority and explaining their costs to people.
“investing in institutions that work for the majority of your subjects, even if indirectly, like they have to pay a cost for them”
Listen from 3:41:27
Anthony Kaldellis
Kaldellis contends that much of the world does not believe the stated goals of American leaders regarding war, citing claims that the Afghanistan invasion was a feminist war.
“I don't think most of the world even believes, you know, what American leaders say their goals are, especially when it comes to like war”
Listen from 3:44:27
Lex Fridman
Fridman argues that the late 20th and 21st centuries will be seen as a period of human flourishing by most measures.
“unquestionably this period in history, the 20th century, The late 20th century and the 21st century will be seen as the flourishing of humans”
Listen from 3:56:25

People

In the conversation

Lex FridmanAmerican podcaster and AI researcher; same host, second diarization label covering the interview segments
Anthony KaldellisHistorian of the Eastern Roman (Byzantine) Empire at the University of Chicago and author of "The New Roman Empire"

Discussed

Constantine the GreatRoman emperor blamed for altering Christian practice through the Council of Nicaea
Justinian IEastern Roman emperor (527–565) known for his law code, conquests and Hagia Sophia
DiocletianRoman emperor (284–305) who created the Tetrarchy and reformed taxation and administration
CaracallaRoman emperor who issued the 212 AD edict extending citizenship
AugustusFirst Roman emperor, founder of the principate
HeracliusEastern Roman emperor who defeated Persia but lost provinces to the Arabs
TheodoraEmpress and wife of Justinian I
Leo III the IsaurianEastern Roman emperor who defended Constantinople against the Arab siege of 717–718
Khosrow IISasanian Persian shah who waged a war of conquest against Rome
HadrianRoman emperor who selected Marcus Aurelius's line of succession
Niccolò MachiavelliItalian Renaissance author of The Prince, namesake of Machiavellianism
AurelianThird-century Roman emperor who reunited the fractured empire
CrispusSon of Constantine, executed by his father
Robin PiersonHost of The History of Byzantium podcast

Topics

From the publisher

Anthony Kaldellis is a historian of the Roman Empire and author of “The New Roman Empire”, a comprehensive history of the Byzantine Empire (Eastern Roman Empire). Thank you for listening ❤ Check out our sponsors: https://lexfridman.com/sponsors/ep498-sc See below for timestamps, transcript, and to give feedback, submit questions, contact Lex, etc. Transcript: https://lexfridman.com/anthony-kaldellis-transcript CONTACT LEX: Feedback – give feedback to Lex: https://lexfridman.com/survey AMA – submit questions, videos or call-in: https://lexfridman.com/ama Hiring – join our team: https://lexfridman.com/hiring Other – other ways to get in touch: https://lexfridman.com/contact EPISODE LINKS: Anthony’s Books: https://amzn.to/49AX7Q1 Anthony’s Publications: https://kaldellispublications.weebly.com Anthony’s University of Chicago page: https://classics.uchicago.edu/people/anthony-kaldellis The New Roman Empire (book): https://amzn.to/3PTFTqk Streams of Gold (book): https://amzn.to/4fgRMRq Byzantium & Friends Podcast: https://byzantiumandfriends.podbean.com/ The History of Byzantium Podcast: https://thehistoryofbyzantium.com/ SPONSORS: To support this podcast, check out our sponsors & get discounts: Upwork: Platform for hiring freelancers. Go to https://upwork.com/lex Fin: AI agent for customer service. Go to https://fin.ai/lex BetterHelp: Online therapy and counseling. Go to https://betterhelp.com/lex LMNT: Zero-sugar electrolyte drink mix. Go to https://drinkLMNT.com/lex Shopify: Sell stuff online. Go to https://shopify.com/lex Perplexity: AI-powered answer engine. Go to https://perplexity.ai/ OUTLINE: (00:00) – Introduction (00:11) – Sponsors, Comments, and Reflections (08:45) – The Roman Empire and the Byzantine Empire (12:42) – 2,200 Years of Roman History (33:06) – Power, violence, and civil war (54:20) – Edict of Caracalla (1:07:17) – Crisis of the Third Century (1:21:45) – Constantine and the new Roman Empire (1:33:46) – Christianity in the Roman Empire (1:59:14) –…

Summary, chapters and key points were generated from the episode transcript on October 31, 2026. Quotes are checked word for word against the transcript.

Categories: History·Christianity·Government