New Dates for the Pre-Roman Iron Age

C.K. Jensen’s relative chronology for the Pre-Roman Iron Age (2005:163)

One of my specialisms is the chronology of the Bronze & Iron Ages, so I’m always keen to read new work in this field. Recently, Helene Agerskov Rose and John Meadows have published a long paper in PloS One (not a common venue for Scandy archaeology) about urn burials at three sites in central Jutland.

The consensus that the new paper enters into dialogue with rests mainly on one book and two journal papers. Using correspondence analysis, Claus Kjeld Jensen (2005) established a robust four-phase relative chronology for Pre-Roman Period artefacts. Using radiocarbon dating on cremated bones, a research group with Jens Olsen and Karen Margrethe Hornstrup as lead authors (2011, 2012) nailed down the absolute date for the first Iron Age burials within the modern Danish borders to the 520s cal BC. I blogged about their second paper here.

Relative chronology answers the question “In what order were these artefact and structure types productive?” Absolute chronology answers the question “In what calendar decades did previously identified major shifts in artefact and structure types occur?” What Rose & Meadows offer here is a mostly extremely solid set of absolute dates for Jensen’s phases.

Before we go into the details, note that the Iron Age is not defined by the first appearance of iron objects generally. We have known for ~150 years that Late Bronze Age metalworkers in Scandinavia used small amounts of iron. The definition rests on cutting tools. Late Bronze Age = bronze & flint knives, occasional iron jewellery. Early Iron Age = iron knives, occasional bronze jewellery. A problem is that when working specifically with Early Iron Age burials, the knives that we know were in use are extremely rare as grave gifts.

Like iron jewellery, urn burial was an invention of the LBA. Some urnfield cemeteries started before the Iron Age, in the LBA, on top of EBA barrows. This has also long been known. This is the normal location for LBA urn burials regardless of what happens later around the barrow. Rose & Meadows anchor the start of their urnfields with burials inserted secondarily into an Early Bronze Age barrow. “Burials from Aarupgaard urnfield are modelled in a sequence based on typo-chronology with an initial ‘founding phase’ with burials U3330, U3341 and U3869 that were interred within an existing Bronze Age mound. Their funerary urns resemble LBA pottery, and although the pins are made of iron, they are typologically closer to LBA types” (p. 31). This is another way of saying that these three graves are Late Bronze Age burials with iron jewellery. Not Iron Age burials. At Aarupgaard, an Early Iron Age urnfield cemetery later accreted seamlessly next to the barrow.

But here’s a major problem with the study. Rose & Meadows have decided a priori (incorrectly in my opinion) that all urn burials at Aarupgaard are Iron Age burials, and that all Jutish urnfield cemeteries start after the end of the Bronze Age. “… we model a transition period following the end of Bronze Age period VI and before burial activity at Aarupgaard, Aarre and Søhale urnfields started. The model shows the transition occurred in the 7th century BC (690–604 cal BC at 68.2% probability), c.50-150yr earlier than usually assumed …” (p. 46).

No. What happens some time in 690–604 cal BC is not that the Iron Age begins. It’s that the Aarupgaard urnfield cemetery begins. On top of an EBA barrow. As is typical for LBA urn burial. At a time when there is 50-150 years left of the LBA. Danish specialists on the Early Iron Age know this perfectly well and do not need the advice of any Swede on this point. If one of them had/has peer-reviewed the manuscript, they certainly would have / did point this out.

Such an earlier end for the Bronze Age is thus not warranted. But furthermore, the claim on p. 46 that it would leave little time for LBA Per. VI reveals that Rose & Meadows have not read the Olsen-Hornstrup papers attentively. (They don’t even cite the 2012 paper.) The Olsen-Hornstrup team moved the start of BA Per. VI back to 800 cal BC. The preceding Per. V is really short. There is thus ample time for Per. VI regardless of when we believe that the Iron Age started.

The issue “whether per. VI should instead be understood as a transitional phase between the Bronze and Iron Ages” (p. 47) is not one of chronology. Per. VI is a typologically distinct phase of relative chronology. We might label it Final Bronze, Initial Iron, Bronze-Iron Transition, we might label it Søren Kierkegaard or Hanne Boel or Fedtmule. This is cosmetics. It’s still the phase between BA Per. V and Jensen 2005 phase I. Renaming Per. VI is equally pointless for the purposes of chronological research as are the perennial attempts to start calling the period AD 750-790 a part of the Viking Period. We might as well call Jensen 2005 phase I “BA Per. VII”.

In my opinion, then, we should reject Rose & Meadows’ 7th century absolute date for the start of the Iron Age. Their lasting contribution is instead the date for the start of Jensen 2005 phase II, with Holstein pins and kuglefibel brooches. Jensen (2005) did not have much data to go on, but he set this provisionally to about 200 cal BC. Rose & Meadows, on the basis of an enormously enlarged data set, now place the start of this phase in 325–286 cal BC (p. 47). Let’s call it the 300s decade, 309-300 cal BC. It’s the only date during the PRIA you really need to know.

Bibliography

Author: Martin R

Dr. Martin Rundkvist is a Swedish archaeologist, journal editor, skeptic, atheist, lefty liberal, bookworm, boardgamer, geocacher and father of two.

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