An atlas of the patterns history keeps repeating.

Two moments in history rarely rhyme in their surface detail – the language, the technology and the borders are always different. What can rhyme is the machinery underneath: how power is concentrated, how contested it is, how institutions hold or fray, how a society sits between openness and control.

The atlas compares that machinery. A strong match means the deep structure of two periods resembles one another – even when they sit centuries and continents apart. It is a claim about form, never about identical events.

The method has three moves, each kept simple on purpose.

1. 1

   Describe

   Each country-era is reduced to a common profile – a fixed set of structural factors drawn from political and economic life, every one placed on the same normalized scale so that distant eras become directly comparable.

2. 2

   Compare

   Those profiles are treated as points in a shared space. The closer two profiles sit, the more their structure agrees – and that closeness becomes a single similarity score.

3. 3

   Read what followed

   For a chosen period we look at what tended to come next for its nearest analogues, and weight those outcomes by how close each analogue is. The result is a weighted analogy, offered as a distribution of possibilities – never a single prediction.

The profiles are built on established, peer-reviewed scholarship in comparative politics and economic history – the kind of long-run academic measures researchers use to compare regimes and economies across time. Those figures are normalized onto shared scales, cross-checked against one another, and smoothed into era-length snapshots so that a single number stands for a stretch of years rather than a single event.

Where the record is thin – as it always is the deeper back you go – the profile carries more judgement and more uncertainty. Treat the oldest eras as sketches, the recent ones as photographs.

• It is a lens, not a verdict. A close twin is an invitation to look closer, not proof that two periods are the same or that one’s fate is the other’s.
• Patterns are not prophecy. The trajectories show what has followed similar structures before. History is not obliged to repeat, and the atlas never claims it will.
• Simplification is the point. Compressing an era into a profile throws away enormous richness. That loss is deliberate – it is what makes far-apart periods comparable at all – but it is a loss.
• No side is being taken. Placing two periods near each other describes their structure. It is not a moral equivalence, an endorsement, or a political argument.