Digging up the past

Everything we know about the Ancient World reaches us through sources, and this topic asks you to classify them precisely. A primary source was created during the time being investigated: a stone tool, a burial, an inscription, a coin or a letter. A secondary source is a later interpretation built from primary material, such as a textbook, an excavation report or a documentary.

The syllabus also separates ancient sources, produced up to the end of the Middle Ages, from modern sources produced afterwards, including historiography, reconstructions and websites. A Roman historian writing about events three centuries before his birth is therefore ancient but secondary.

Finally, sources can be archaeological (material remains recovered from the ground or from sites) and literary or non-literary: literary sources are written texts such as histories, poems and letters, while non-literary sources include objects, art, buildings, human remains and landscapes. For Ancient Australia almost all evidence before European contact is non-literary and archaeological, while knowledge held and transmitted by Aboriginal and Torres Strait Islander communities is a living source that must be used with the community's permission.

Authentication is the process of establishing that a source is what it claims to be and dating it securely. Scientific (absolute) dating gives an age range in years: radiocarbon dating measures the decay of carbon-14 in once-living material and works back to roughly 50 000 years; optically stimulated luminescence (OSL) estimates when sediment grains were last exposed to sunlight; dendrochronology counts tree rings.

Comparative (relative) dating places evidence in sequence without exact years: stratigraphy assumes lower layers are usually older, while typology compares an object's style with securely dated examples. Historians also cross-reference ancient sources, checking one account against other texts, inscriptions or archaeology. No single method is decisive; confidence grows when independent methods agree.