As mentioned above Argyll has previously been described as being a black hole in terms of modern archaeological research (Haselgrove et al. 2001). Future work on the Iron Age in Argyll should incorporate many of the Scotland-wide research recommendations recently outlined by Scottish Archaeological Research Framework (ScARF 2012).
What seems self evident is that, apart from a few stray finds, the vast bulk of evidence we have for Argyll's Iron Age comes from excavation whether antiquarian, later research or commercial projects. As a field archaeologist it probably comes as no surprise that I would argue that it is equally self evident that if we wish to add to the picture and attempt to address some of the ScARF research recommendations, more excavation work needs to be undertaken.
Sample excavation of previously unexcavated sites would provide a means of obtaining a primary-stage analysis of the Iron Age settlement sequence in Argyll, essentially evaluating the existing resource of which less than seven percent has had some sort of archaeological investigation. From this basis potentially informative sites could be targeted for more extensive excavation, employing the wide-ranging analytical techniques available to the modern excavator. Another and perhaps less intrusive method of enhancing the existing database would involve the reopening of trenches from previous excavated sites which could potentially date internal sequences and give chronological context to previously recovered artefacts; Appendix 2 suggests some sites that would warrant further investigation.
It is clear from the results of rescue and commercial archeology that there potentially remains a large 'invisible' settlement component in the Iron Age, as perhaps in other periods, which has now to be considered when trying to model any demographic and settlement patterns. The recent excavation of several groups of timber roundhouses originating in both the traditionally demarcated Bronze Age and Iron Age periods in Argyll, may give us important insights into the possible chronological relationships between the development and use of the roundhouse and the building of forts, brochs and duns. However, more of the latter need to be investigated with the hope that more of the former come to light. A key area to develop is the means to predict, prospect and discover these previously invisible aspects of Argyll's Iron Age.
The apparent lack of artefactual material within many excavated Iron Age sites is likely due to the lack of survival of specific types of artefact particularly organic material. Further investigation of crannogs and wetland sites in Argyll as elsewhere has the potential to give a more complete understanding of material culture in this period as well as shedding much needed light on environmental profiles and natural resource exploitation.
7.5.2 Landscape Survey and Environmental Research
Site specific excavation will need to be accompanied by more intensive survey of areas surrounding them; indeed it could perhaps be argued that survey work should always precede any excavation. The incorporation of landscape and waterscape analysis, representing the need to understand the influence of the sea and freshwater bodies as a central part of travel, trade and the contemporary experience of living in Argyll, should accompany such survey work. This might also give us better insights into the continuity of settlement and perhaps shed light on the nature and chronology of boat nausts, enclosures and field systems and their relationship to potential Iron Age structures. Of course identifying Iron Age land use patterns surrounding any specific Iron Age habitation site is fraught with problems given that the available agricultural land in Argyll, as elsewhere in the Highlands, is physically constrained by geography and thus limited within the same parcels of land reworked over time. Identifying regional relic land-use patterns overtime would be very profitable and targeting smaller land units for intensive survey and excavation might enable chronological landscape profiles to be established.
Recent study of the late prehistoric environment in Glen Add suggested a relatively stable environment in this locale up to 650 BC. Thereafter, if Argyll followed patterns seen in Ireland, it may be that the area suffered from climate deterioration in the form of increased rainfall. Increased storminess may have had an impact on sea-going travel. If this was the case then any such deterioration may have led to the loss of marginal land previously exploited for crops and grazing, with increasingly boggy ground on the glen floors compounded by the loss of higher cultivable land. The extent of the local population is of course unknown but even with a relatively stable or slightly growing population such a loss of land would have led to increased pressure on the control of land tenure. The environmental evidence for this period however is local and patchy for example in some places in Argyll there appears to be a loss of tree cover around c.500 cal BC this perhaps increasing towards the BC-AD boundary. To this extent it is crucial that we have better modelling of climate change in this period for Argyll along with a better understanding of potential effects of sea level change.
7.5.3 Re-assessment of older material
As elsewhere in Scotland, Argyll has informative Iron Age assemblages from several sites that in many cases lack chronological definition. Most of these come from excavations and, as recently suggested by Alexander among others, would warrant re-examination providing a dating framework whereby the existing archival and artefactual material could be re-interpreted and synthesised using scientific techniques not available to the original excavators (Alexander 2012).
The recent analysis of glass toggle beads mentioned above show how current scientific techniques can shed light on the origin and manufacture certain artefacts, while accompanying study of their distribution show a distinct bias in western Scotland the Isle of Man and Ireland, perhaps indicating intra regional contact in the late pre-Roman Iron Age.
Within Argyll there appears to be regional or sub regional differences in certain aspects of material culture present in the Iron Age. This is perhaps most obviously noticeable with the presence/absence of decorated Hebridean or insular pottery, this difference is perhaps reflected in the apparent absence of broch and wheelhouse architecture in the southern Hebrides and mainland Argyll.
Plain pottery however does occur and these assemblages need to be studied to see if any typologies or other details in construction, use and deposition can be teased out. Other artefact groups equally require modern re-evaluation and synthesis.
New research work along with information that will undoubtedly continue to be produced by commercial archaeology will allow broader regional patterns to be discerned across Argyll in the Iron Age, whereby the region can be better compared to more exhaustively studied regions in Scotland and elsewhere.