The EARMEDCASTILE project, based at the University of the Basque Country, has received funding from the European Union's Horizon 2020 Research and Innovation Programme, Marie Sklodowska-Curie Action (grant agreement 656540); http://earmedcastile.blogspot.com).

The main goal of the project is to study the formation and transformation of the local and central political institutions of northern Iberia during the Early Middle Ages, analysing craft production, exchange systems and consumption patterns as markers of social and political complexity. In order to achieve these aims, the project adopts an interdisciplinary approach, with an emphasis on archaeological science techniques, to examine the lifestyles of social elites and the means by which they extracted revenues, as well as other archaeological indicators of power and influence (for a preliminary report, see Grassi Reference Grassi and Quirós Castillo2016).

The main innovations of the project are:

• • A social theory approach to the emergence and collapse of local and central political institutions.

• • An archaeological perspective on political complexity in the hitherto unexplored area of northern Iberia (Quirós Castillo Reference Quirós Castillo2016).

• • An interdisciplinary evaluation of the significance of different archaeological markers for the analysis of early medieval states.

• • A territorial definition of early medieval states based on commercial exchange.

• • A comparison of early medieval northern Iberia with other European contexts.

In recent years, large-scale research and rescue archaeological projects have yielded considerable information regarding early medieval sites and assemblages. Based on this new evidence, we will analyse the ceramic material from 15 sites dated to the early medieval period (sixth to tenth centuries AD) (Figure 1).

Figure 1. Location of the sites included in the EARMEDCASTILE project.

The first phase of the project focuses on cataloguing material and sampling ceramics, prior to archaeometric analysis. We are working on a collection of almost 15 000 fragments, totalling 118kg and representing 1314 different vessels (Figure 2). The 15 selected sites are located in three different geographic areas in the north of Spain: the upper Ebro, the Miranda of Ebro basin and the Alava Plain. Nearly all the sites are long-term settlements, the earliest occupation phases of which date back to the protohistoric or Roman periods. All were continuously occupied throughout the Middle Ages. The study region includes the historical County of Castile, which existed between AD 816 and 931, and which depended on the Kingdom of Asturias (Estepa Diez Reference Estepa Diez2009) (Figures 3–4).

Figure 2. Characterisation of the study sites.

Figure 3. Example of inter-regional circulation: medieval jug from Zaballa (eighth to ninth centuries AD), and microphotograph showing the fabric.

Figure 4. Locally produced pottery: medieval pot from Aldaieta (sixth to seventh centuries AD), and microphotographs showing the fabric (parallel nicols, magnification 2.5×).

The project involves a large-scale archaeometric study of early medieval ceramics in Castile, with the aim of identifying the key production centres (Grassi & Quirós Castillo in press). Special attention is paid to categories such as red-painted pottery (Figure 5), which travelled widely across the northern Iberian Peninsula (upper Ebro Valley, western Pyrenees), as indicators of inter-regional exchange (Fornacelli & Grassi in press).

Figure 5. Ebro Valley-produced pottery: red-painted from Poza de la Sal (eighth to ninth centuries AD), and microphotograph showing the fabric (parallel nicols, magnification 2.5×).

The scientific examination of the samples includes petrographic, mineralogical and textural analysis of the fabrics, as well as inclusions, using optical microscopy. Chemical analysis (ICP-MS and ICP-OES) is also undertaken in order to collect further information about the properties and the provenance of the raw materials. All data are stored in the online GIS platform, Medieval Archaeology of Northern Iberia (ARMENOP; http://worldmap.harvard.edu/maps/ARMENOP), created by the Research Group on Cultural Heritage and Landscapes (http://www.ehu.es/en/web/culturalheritage/home).

EARMEDCASTILE's goal of linking the analysis of local-scale events with wider political institutions, and their ongoing formation and collapse, poses several challenges (Escalona Monge Reference Escalona Monge, Escalona Monge and Reynolds2011). Taking into account that this region was characterised by an absence of urban centres, by geographic fragmentation caused by natural barriers, and by the lack of inter-regional exchange hubs such as emporia, it is, in general, plausible to suggest the existence of direct marketing mechanisms, of varied levels of complexity. On top of this fragmented socio-political system, the short duration of centralised polities also influenced the production, consumption and distribution of pottery. For example, existing pottery-production and -circulation systems survived into the Visigothic period, starting in the sixth century, but were complemented by new productions with their own distributions, responding primarily to social differentiation within village settlements. Later, from the eighth century onwards, the internal transformation of these villages coincides with the emergence of new productions and with a large expansion in circulation, which extends into other regions. This trend seems to continue with the formation of the County of Castile in the tenth century, and shows a progressive intensification and standardisation of local distribution, while inter-regional exchange of ceramics is increasingly indicative of the emergence of new local powers rooted in the settlements of the study area.