Theory Key ideas

History is the study of the human past through evidence. It is not the past itself (which is gone) but a disciplined reconstruction of it. Two distinctions organise the whole subject:

• Primary sources — produced at the time under study: charters, letters, coins, pottery, tax rolls, inscriptions, photographs, bones. Secondary sources — later accounts about the past, such as a modern textbook or scholarly article.
• History (the study of the past through written records) versus prehistory (before writing, studied mainly through archaeology). Writing appears in Sumer c. 3200 BCE, which is why that date is the conventional dawn of recorded history.

Historians ask of every source the same battery of questions — often taught as the 5 Ws: Who made it, When, Where, Why (purpose and audience), and What it actually claims. From these we judge reliability, bias (a source's slant, which does not make it useless — it makes it a piece of evidence about its author), and provenance (the chain of custody proving a source is genuine, not forged).

Two technical ideas underpin dating and interpretation:

• Chronology — the CE/BCE (formerly AD/BC) system pivots on a notional Year 1; there is no year zero. Radiocarbon dating (measuring decay of carbon-14, half-life ~5,730 years) and dendrochronology (tree rings) give absolute dates for prehistory.
• Historiography — the history of history-writing: how interpretations change over time. The same event (say, the fall of Rome) has been explained by moral decline, economics, disease and migration by different generations of scholars.

Explanation Why it matters

Beginners imagine history is "just what happened." But we never have direct access to the past — only to its traces, and those traces are partial, damaged and made by people with motives. A Roman emperor's coin proclaiming "peace" is not evidence that there was peace; it is evidence that the emperor wanted to be seen as a peacemaker. Learning to read a source for what it reveals despite itself is the single most important skill in the subject.

This is why two honest historians can disagree. They are not choosing different facts; they are weighing the same imperfect evidence and asking different questions of it. Recognising that history is interpretation constrained by evidence — not free invention, but not certainty either — is what separates the historian from both the propagandist (who ignores inconvenient evidence) and the naïve reader (who believes the last book they read).

Practical Source analysis — worked example

Let us analyse a genuinely tricky primary source and reason through it as a historian would.

Step 1 — Provenance & the 5 Ws. Who: Julius Caesar, Roman general. When: written during his conquest of Gaul, 58–50 BCE. Where/what: a first-person campaign account. Why: crucially, Caesar published these dispatches in Rome to build his political reputation while he was away.

Step 2 — Read for purpose and bias. Caesar writes in the third person ("Caesar did…"), a rhetorical device to sound like an objective report rather than self-promotion. He praises the Belgae as "bravest" — but notice the effect: the braver the enemy, the greater his own victory over them. Bias here is not a flaw to discard; it is the very thing that tells us what Caesar wanted his Roman readers to conclude.

Step 3 — Cross-examine. What can we trust? Geographic and ethnographic detail (that the Belgae border the Germans) is plausibly accurate and corroborated. What must we treat with caution? Any claim that flatters Caesar or justifies the war. We would corroborate against archaeology (Gallic oppida, coinage) and later writers.

Step 4 — Verdict. Source A is a reliable record of Roman perceptions and of Caesar's self-presentation, and a useful but partial record of Gallic society — to be trusted only where it is disinterested or corroborated. That two-sided judgement — reliable for what? — is the model answer.

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