That is the title of an intensely fascinating book by British historian Adrian Goldsworthy. The collapse of the Roman empire in 476AD has exercised the minds of historians, sociologists and archaeologists for years. Goldsworthy’s book is admirable for the depth of scholarly coverage and its easy accessibility for the interested reader. While posing the big question in the early chapter – the introduction is called literally “The Big Question”, Goldsworthy provides a sweeping overview of the prolonged internal decline and repeated external pressures that eventually culminated in the fall of the Roman superpower.

In 476AD, the last emperor of the Western Roman empire, Romulus Augustulus, was deposed by an invading Germanic general. The various German tribes, organised into a confederacy, had been exerting tremendous pressures on the already-tottering Western Roman empire. The deposition of Romulus merely consolidated an extended process of ‘slow death’ as Goldsworthy puts it. The significance of the 476AD terminus has been questioned by many historians, and Goldsworthy answers the persistent question of why the Roman empire collapsed, but continued, albeit in truncated form, in the east with the Byzantine empire. The Byzantines never referred to themselves in that way, always insisting that they were the true inheritors of the Roman empire.

Goldsworthy proceeds to unfold the narrative of the economic and political decline of the Roman empire from 180AD, with the death of Marcus Aurelius, the philosopher-emperor. He examines the crisis of the third century, when from the end of the Severan dynasty to the advent of Diocletian in the mid-280sAD no less than sixty people claimed the title of emperor. While Goldsworthy does not overstate the extent of the crisis, he does state that the Roman empire underwent significant stresses, not least of which are the foreign invasions. The Sassanid Persian empire in the east attacked Roman territory, and the western provinces of Gaul, Britain and Hispania broke away to form their own Gallic confederation. The Roman provinces of Syria, Palestine and Egypt rebelled and formed their own Palmyrene kingdom under the Queen Zenobia. This is the first Semitic kingdom, and Goldsworthy goes into some detail about the importance of Palmyra for the Romans as a trading post and its importance as a magnificent city. Zenobia and the Palmyrene empire mounted a serious challenge to Roman rule in the mid-third century.

Queen Zenobia was an interesting political player in her own right, and she is one of several women rulers that Goldsworthy examines in his book. He has a whole chapter on “Imperial Women” where he elaborates the intrigues and political power of several important women during the crisis of the third century. There were several energetic and politically forceful women who controlled many of the changing emperors during the third-century crisis.

Repeated invasions by the so-called ‘barbarian’ tribes – the Goths – exacerbated the crisis of the Roman empire. However, the Roman still had enough resources and political will to overcome each foreign threat, restore Roman rule to rebellious provinces and restore the legitimacy of imperial rule by the end of the third century. The crisis had been severe, and it indicated to the Roman elite that it could no longer rule in the old way; the way that Rome was ruled in Marcus Aurelius’ time.

Diocletian rose to power by the end of the third century, and he initiated a series of reforms that would have far-reaching implications for the future of the Roman empire. Goldsworthy details the creation of the tetrarchy – a system of multiple rulers for the empire – and the administrative division of the geographically vast empire into units of territory to make them more easily governable. Diocletian expanded the Roman government and created new provinces, and with them new governors. His reforms, while successful in the short-term, did not lead to lasting success. Diocletian resigned from office, and all the old conflicts returned, especially the internal divisions with different commanders, summoning military support from their own provinces, launching bids for supreme imperial power.

Goldsworthy delves into the transformation of the late Roman empire from paganism to Christianity under the innovative emperor Constantine. The conversion to Christianity has attracted a great deal of attention from historians of the Roman period, and Goldsworthy documents the trials and tribulations of the Christians from the Diocletianic persecutions to the eventual Edict of Toleration by Constantine I. The pressures of successive and increasingly organised Gothic tribes took their eventual toll on the Roman empire. Constantine famously constructed the alternative capital of Rome at Constantinople, and this move along with the formal administrative division of the Roman empire into the Latin-speaking West and the Greek-speaking East demonstrated the decline of Rome’s importance as an imperial capital.

An interesting sub-story to the decline and fall of Rome is the later’s retreat from the province of Britainnia. While the island was still part of the Roman empire, and leading Britons still felt an attachment to Roman rule, the province did not have an actual governor for about the last 25 years of imperial rule on the island. Goldsworthy elaborates that many British aristocrats sided with Roman rule and did very well for themselves. The Romans left their unmistakable cultural imprint on the province, and after Rome withdrew from the island in 410AD, the remaining British elites did their best to maintain Roman cultural customs and practices. Britannia was on the margins of the empire, and the majority of the population eventually acquiesced to Roman rule, even though there were serious uprisings throughout the Roman occupation. Britain fragmented into separate communities after the Roman exit in 410-411, so Goldsworthy is careful not to retrospectively impose a British nationalist consciousness on the Britons of the Roman period. While there was a distinct Britannia province, there was not necessarily a unifying sense of British nationalism.

Goldsworthy details the debates among historians regarding the collapse of the Roman empire, while never detracting from the historical narrative. Some historians have challenged the ‘decline and fall’ thesis, preferring to speak of a gradual transformation rather than a collapse. Goldsworthy concludes by literally providing “A Simple Answer”. The Western Roman empire collapsed in the fifth century, and those historians who talk of a ‘transformation’ rather than a collapse admit this fact. While the Eastern half of the Roman empire survived for another thousand years as Byzantium, it never approached anything like the superpower status of the Romans. It was merely one strong power among several competing powers, and lost territory to successive conquests by Islamic Arabs, and eventually was overrun by the all-conquering Ottoman Turks.

I think the book could have examined one facet of Roman society that was so ubiquitous and important it needs further elaboration; slavery. Goldsworthy does mention slavery in Roman society, but summarily dismisses its importance. While he states that ‘Slavery was a fact of life in the Roman Empire, and indeed every other ancient society’, he goes on to say that ‘Slaves seem to have been rare as the main labour force outside the large estates of Italy’. I think Goldsworthy misses the mark here.

The use of slaves, while initially tempting and productive, had outlived its utility by the late Roman empire. The Roman polity, while unified against outsiders, was divided within itself into the slaves, and the slave-owning landlord class. Slavery does not provide any incentive to innovate and develop new means of production; the slave only works through the menace and use of violence. The plebeians, poor freemen, had their own quarrels with the upper classes, and fought to assert their political rights. However, any society based exclusively on slavery is bound to eventually fail economically. Slave-owning could not keep up with trade and free labour as an economically viable method of production and exchange.

The cost of keeping an empire swollen by conquests and slaves was so great, that the army became the one force capable of keeping the slaves in line, and the plebeian freemen fighting for conquests. The emperor, also the military commander-in-chief, was the source of patronage. Nepotism and corruption flourished in an environment where anyone could seek favours by connecting with people in power. Increasing numbers of emperors in the late Roman empire originated in the military. Military commanders in the provinces demanded loyalty from their subjects, and used that loyalty to launch challenges to the emperor’s central rule.

Periodic rebellions by slaves meant that productivity was interrupted, and with the decline in production, so also trade declined. Slaves, worked to death within a few years, had to be periodically replaced by new military conquests. Those conquests were carried out by plebeians in the army, the very people who would lose out to slave-owning production. The empire was economically rotting from within, making it more vulnerable to attacks from outside. The huge estates of the landlords began to resemble large, semi-autonomous villas or manors, which is the hallmark of a feudal society. The slave-owning Roman society could not sustain itself.

The decline and fall of the Roman empire is the source of many historical lessons, and naturally comparisons are made to understand the fall of other empires. The British were fond of comparing their nineteenth-century empire to the Roman, and currently many commentators draw comparisons with the United States and its financial empire. There certainly are lessons to be learned, particularly about imperial hubris when an empire’s policy-makers believe they can conquer any territory and underestimate the degree of resistance by subject peoples. Witness the hubris of the United States in its blundering into Iraq and Afghanistan, wars which were based upon wildly optimistic expectations of quick victories but have become terrible quagmires.

There are lessons to be learned about overextending finances into costly unwinnable wars, that drain a society of sorely needed money for internal repair and social services. But Goldsworthy warns against drawing historical analogies too closely. There are broad similarities between the US and Roman empires, but there are enormous differences. While Rome was based on slave-owning and slaveholding landed estates were the norm of production, the US is a major capitalist economy with huge multinational corporations extending into most areas of the globe. Whether the US follows exactly the same course as the Roman empire remains to be seen, but the past does contain valuable lessons if we are to avoid repeating it. Empires inevitably endure a prolonged period of decline, challenged by major competitors. The emergence of the BRIC countries (Brazil, Russia, India and China) and the development of the Shanghai Cooperation Organisation as a counterweight to the US ambitions signals the end of a unipolar world. The late Roman empire had several economic and military challengers, such as the Persians, the Hunnic empire and the Germanic confederations.

Goldsworthy’s book is a remarkable and welcome addition to the ongoing debate about why the Roman empire collapsed. As he makes clear, it was a prolonged process, punctuated by military crises and foreign military defeats. He analyses the internal decline as well, stating that ‘each civil war cost the empire’. With each internal conflict, the Roman empire’s authority was weakened, making its conquest ever-more tempting to its external enemies. While the Goths and ‘barbarian’ invaders struck fatal blows, they struck an empire already enfeebled by decay. Goldsworthy’s book is necessary reading for anyone who wishes to explore the reasons for the corrosion and ultimate collapse of the Roman empire.