IMPERIAL: What Empire Chronicles Leave Out

Every empire in history has told the same story about itself: we brought order, we built roads, we made the trains run on time. What the chronicles leave out is the spreadsheet. Who actually got richer? How long did the prosperity last? And when it ended, how fast did it go?

Those questions have answers now. The Maddison Project Database — the most comprehensive long-run economic dataset ever assembled — lets us put Rome, Britain, the Ottomans, Imperial China, the Mongols, and Habsburg Spain on the same chart and ask: what does empire actually look like as an economic system?

The answer is not what the history textbooks imply. GDP goes up. Real wages mostly don’t. The rise takes centuries. The fall takes decades. And in every case, the institutions built to extract surplus during expansion become structurally incapable of sharing it during maturation. That’s the pattern. Six empires. No exceptions.

Research question

When empire is measured through long-run GDP per capita and real wages, who captures the surplus: the imperial core, ordinary workers, or institutions built for extraction? This report asks whether Rome, Britain, the Ottomans, Imperial China, the Mongols, and Habsburg Spain show comparable trajectories once their economic series are indexed and capped to historical lifespans.

The observational question is not whether empires built infrastructure or expanded trade. It is whether aggregate output translated into living standards, how quickly imperial GDP peaks unwound, and whether the extraction gap between GDP and wages is visible in the best available long-run economic evidence.

Gdp Per Capita Across Empire Cores

Gdppc All Empires

For the first 1,800 years of this chart, five of the six empire cores are essentially stationary. Rome peaks early and declines. The Ottomans and Imperial China drift sideways for centuries. Habsburg Spain — despite controlling the most silver-producing territory in human history — never generates a GDP breakout. The Mongol blip in the 1260s appears and vanishes within a century. The chart’s visual drama is entirely a British phenomenon, and it doesn’t begin until roughly 1800. That flatness is not a data artifact. Pre-industrial economies were governed by a hard ceiling: agricultural productivity. Every empire eventually hit the same constraint — you can conquer more land, you can tax more efficiently, you can build better roads — but you cannot grow aggregate output faster than the soil can produce food. This is why five empires operating across four millennia produce nearly identical GDP trajectories. They were all playing the same zero-sum game. The temptation when looking at Chart 1 is to conclude that Britain governed better. This is wrong. The British divergence is a technology story, not an institutional one. Steam power — specifically the transition from organic energy (human labor, animal muscle, firewood) to fossil energy (coal) — removed the agricultural ceiling entirely. British GDP per capita in 1900 is not high because of better laws or smarter monarchs. It is high because coal-powered factories could produce manufactured goods at a scale that no farming economy could match, and Britain industrialized first. The Roman GDP line in this dataset is a back-extrapolation built from Maddison (2007), Scheidel and Friesen (2009), and Lo Cascio and Malanima (2009) — the best available estimates, with significant uncertainty bands. At roughly $1,000–1,200 in 2011 USD PPP, the Roman Empire’s peak was genuinely impressive for its era. It represents something like double the GDP per capita of its contemporaries and suggests a level of market integration — trans-Mediterranean trade, monetized labor, professional armies — that would not reappear in Europe for a thousand years after the Western collapse.

Rise Fast, Fall Faster

Empire Lifespan Indexed

Chart 2 removes the distortion of absolute scale. By indexing every empire’s GDP per capita to its own peak (peak = 100) and aligning on a ±200 year window, we can compare trajectories directly. What emerges is not six different stories — it’s one story with six variations in speed. The left side of the chart (years before peak) shows the consolidation phase. Resources flow inward, administration tightens, transaction costs fall, and GDP rises. The right side (years after peak) shows the extraction phase running out of road. The institutional machine keeps turning, but the returns on further centralization diminish, external shocks go unabsorbed, and GDP falls. Every empire, on this chart, is climbing the same mountain. This is the finding that Chart 2 makes hardest to argue with. Every empire in the dataset rises over a period of two to five centuries. Every empire declines in a fraction of that time. Rome takes roughly 300 years from Augustus to Western collapse — but the indexed chart shows that 60% of the GDP loss happens in the last 80 years, after the Crisis of the Third Century (235 CE). Habsburg Spain’s post-peak decline is sharp and early; the empire technically persisted for another century, but the GDP trajectory turned negative almost immediately after Philip II’s peak. The Mongol Empire — the most extreme case — rises from virtually nothing to continental dominance in 60 years and fragments within a generation of Kublai Khan’s death. The Roman line in Chart 2 stands out as the flattest post-peak trajectory — holding above 80% of peak for nearly a century after the GDP maximum. This is not evidence of Roman resilience; it is evidence of how slowly the Western Roman political structure dissolved compared to how quickly the underlying economy had already stopped growing. Walter Scheidel’s work on Roman inequality ( The Great Leveler , 2017) identifies this period as one of elite wealth concentration rather than broad prosperity — the GDP aggregate was holding because the very top of the distribution was insulating itself from the broader decline.

The Extraction Gap

Extraction Gap

Chart 3 is the payoff. By indexing both GDP per capita and real wages to 1500 = 100 for each empire, it shows what happened to the surplus generated by imperial growth — and specifically, how much of it reached ordinary workers versus how much was captured above them. The shaded area between the GDP line (solid) and the wage line (dashed) is the visual measure of extraction: surplus produced but not distributed. In three of the four empires shown, that gap widens dramatically over time. In one — Britain, post-Industrial Revolution — it eventually closes. The British panel is the most complex in Chart 3. From 1500 to roughly 1750, GDP per capita and real wages move more or less in parallel. Then the Industrial Revolution hits. GDP per capita accelerates dramatically. Real wages initially lag, producing the classic “Engels Pause” — the period between roughly 1780 and 1840 when British workers lived through massive productivity growth without real wage gains. But then something unprecedented in imperial history happens: the dashed line catches up. By the late 19th century, British real wages are rising faster than GDP per capita. Britain is the only empire in this dataset where workers at the bottom of the distribution captured a significant share of imperial growth before the empire ended. Habsburg Spain’s wage line is the most damning line on the chart. Starting at approximately 1.8 silver grams per day in 1500, it declines steadily to roughly 1.0 by 1600 and never recovers. This is the period during which Spanish galleons were carrying hundreds of tonnes of silver annually from Potosí and Zacatecas to Seville. The mechanism is the Price Revolution: the flood of American silver raised prices across the European economy while nominal wages failed to keep pace. Habsburg Spain extracted the largest resource windfall in pre-industrial history and distributed the gains almost entirely to the Crown, the Church, and the Genoese bankers who financed imperial debt. The workers got the inflation.

What this file cannot tell you

The Maddison Project has no Mongol Empire country code. The figures here use a population-weighted average of China (CHN, 45%), Russia (RUS, 30%), and Turkey (TUR, 25%) for 1200–1400 CE. Turkey is the closest available proxy for the Ilkhanate’s Persia-Iraq core. This captures broad regional output but understates the empire’s Central Asian footprint. SESHAT Databank remains the most rigorous replacement.

Maddison’s ancient-era GDP figures are back-extrapolations built on archaeological proxies — lead pollution records, shipwreck counts, amphora output. They carry uncertainty bands that would dwarf the point estimates if visualized. The Roman and Han Chinese figures are the best-supported; treat all others as orders of magnitude.

Real wage data is largely unavailable before ~1300 CE, making the extraction gap analysis in Chart 3 impossible for Rome or the early Mongol period. Pre-wage-labor tributary economies did not generate the record types from which wages can be reconstructed.

Mapping a multi-continental empire to a single modern country code (Britain = GBR, Ottoman = TUR) captures the metropolitan core but ignores the periphery. British GDP per capita for the UK does not include what was extracted from India, Africa, or the Caribbean. The chart shows what happened to the empire’s home population — not to its subjects.

What to take away

Six empires. Four thousand years. The curve barely changes. A period of administrative consolidation reduces transaction costs, enables infrastructure at scale, and produces a GDP spike. That spike is real — it shows up in the Maddison data clearly. What it conceals is who captured the gains — and Chart 3 is where the concealment ends.

In every empire with wage data, the extraction gap widens during peak imperial expansion. British GDP per capita grew roughly 150% between 1700 and 1850. Real wages for English laborers grew approximately 30–40% over the same window. The rest went to rents, dividends, and colonial surplus. The Ottoman and Habsburg cases are more extreme. Habsburg Spain extracted the largest silver haul in pre-industrial history and produced domestic wage stagnation. More money in the system; less in the wage earner’s hand.

Chart 2 makes this structural. Every empire takes two to five centuries to build GDP to peak. The fall takes a fraction of that time. The Roman trajectory from Commodus to Western collapse is roughly 300 years — but 60% of the GDP loss happens in the last 80. The Mongol Empire peaks in 1260 and is functionally fragmented by 1350. Speed asymmetry is the rule, not the exception.