The Artisans behind Visigothic Buildings: the Materiality of Identity [1] (pdf)
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Abstract:
Approaching Visigothic artisans in the Iberian Peninsula is not an easy task, since archaeological and art historical studies continue modifying traditional and prevailing views on them. The chronologies of and our understanding about architectural and sculptural elements attributed to this period (the sixth and seventh centuries ad) are being revised, due to the securing of accurate stratigraphic sequences (both from excavated and standing buildings), the uncovering of new materials, the reinterpretation of the relatively few written records, and the introduction, thus, of innovative and fresh theses. Within this frame, although artisans and their knowledge and skills are directly visible in the archaeological record, their identity is only to be approached in an indirect way, in which preliminary hypotheses will have to be reconsidered in the near future.
Essay:
By way of archaeological scholarship on ecclesiastical architecture, and the work of art historians, it has been commonly argued that the artisans responsible for the Visigothic constructions in the Iberian Peninsula (of the sixth and seventh centuries) inherited and were able to preserve previous Roman building techniques and forms, both by copying earlier structures and by reusing extant materials. These Visigothic architects would also have been capable of introducing and employing Byzantine features, which would explain the extraordinary quality of Visigothic architecture and sculpture in relation to contemporaneous productions elsewhere in the Mediterranean. This established interpretation, however, is under scrutiny, as new research, influenced by recent anthropological and archaeological innovations,[2] critically re-analyzes Visigothic architectural and sculptural culture and challenges its chronology, on the one hand, and the ways in which technology was transferred, on the other.[3]
In discussion with that new research, this essay aims to elicit the builders of the sixth and seventh centuries, and to evaluate their technological knowledge, skills and identities. To do so, firstly, the current scholarly situation concerning architecture and sculpture dated to the Visigothic centuries is explained. Secondly, via studies of the preserved constructions of the sixth and seventh centuries, I uncover the knowledge and skills of the artisans by analyzing their qualifications, the materials they employed and how they did so, the instruments they used and how they combined them. This approach will hopefully make it possible to understand the training and experience of these artisans and the actual relation of the architectural products to others from previous and later moments in the history of the Iberian Peninsula. Finally, in consideration of the above, and the written records, a final reflection on the artisans and their identity is postulated.
Explaining Late Antique and Early Medieval Hispanic Churches: Updated Thinking
The discussion that has developed in recent years on late antique (sixth-seventh centuries) and early medieval (eighth-tenth centuries) Hispanic material culture, including here also churches, affects directly our comprehension of the artisans of these periods, and their knowledge, skills and identities. The introduction, in the 1990s, of the stratigraphic method in the study of standing late antique and early medieval Hispanic churches had as its aim a deeper approach to studying this architecture and its characterization and chronology – areas which had been mapped out a long time ago according to stylistic criteria and the information provided by written sources which were hardly ever contemporary and frequently from significantly later. Archaeological records, on the other hand, were rarely taken into account.
In brief, it may be stated that prevailing opinion was based hitherto on the idea of continuity between the architecture and the decorative art of the Iberian Peninsula from late Roman Hispania (fourth-fifth centuries) to the Visigothic period (sixth-seventh centuries), followed by the subsequent Asturian (late eighth-early tenth centuries) and Mozarabic (tenth century) styles.[4] It was felt that Roman traditions, together with Byzantine influence, strengthened by the Byzantine occupation of the south-east of the peninsula during the second half of the sixth century,[5] were sufficient to permit and feed this continuity, which would clearly feature in the material culture dated to those periods. This hypothesis made it necessary to accept that differences in similar architectural and sculptural products between the fifth and tenth centuries were attributable to diverse local contexts, but the technology remained the same and was unaffected by historical changes.
In contrast to this model was an alternative explanation,[6] one based upon the application of the new archaeological method to both excavations and standing buildings, which began to argue that the Islamic conquest of Hispania (711) implied a technological rupture. According to this theory, pre-Islamic, Christian architecture (recorded principally during the period between the late fifth and seventh centuries) was made up for the most part of basilicas built from reused materials, with rough stone masonry and timber roofs. Nonetheless, there is also a group of churches hitherto believed to have been Visigothic and therefore dated to the second half of the seventh century, though not on the basis of any archaeological evidence.[7] Taking into account their architectural features, these need to be re-dated to after the conquest. They should be understood as innovations and therefore be attributed to techniques and artisans which arrived with the Islamic conquest.[8]
This second model aims to demonstrate that these two main architectural groups, pre- and post-Islamic conquest, are necessarily different because they belong to two different contexts. The former is to be understood after the demise of the Roman system and within the framework of a period that witnessed the dismantling of the previous cycle of building production, as is shown by the ending of activities, such as brick manufacture, quarry exploitation and monumental public architecture, and therefore the vanishing of skilled masons, thereby forcing builders to reuse building and sculptural materials and to adopt simpler structures.[9]
The latter was marked by the introduction of Eastern building technology driven by the arrival of trained and skilled artisans and the emergence of new elites which would become the new patrons, thus creating demand. These novel factors lead, for instance, to quarry exploitation, brick production, ashlar stone masonry, and optional reuse material,[10] resulting in the building and decorating of complex vaulted structures being witnessed from then on for the first time since the Roman period. It is, after all, undeniable that if changes are recorded in related production cycles after the Islamic arrival, it would be very hard, and indeed contradictory, to affirm that there were no modifications in architectural and sculptural production and that this was a mere revival of earlier forms and techniques.
It is within the frame of this second explanation that the following argument approaches an understanding of the artisans and their knowledge, skills, and identities.
Artisans and Architecture in the Sixth and Seventh Centuries: Knowledge and Skills
In recent years, archaeologists have uncovered new sixth- and seventh-century urban and rural ecclesiastical constructions (e.g. Santa Eulalia, Mérida; Tolmo de Minateda, Albacete; Silla del Papa, Cádiz), revisited previously excavated buildings (e.g. El Gatillo, Cáceres; Segóbriga, Cuenca), further excavated others (e.g. Casa Herrera, Badajoz), and re-evaluated late antique written records (both epigraphic and palaeographic) in light of new discoveries.[11] This collective evidence presents fresh perspectives on sixth- and seventh-century urban and rural Iberian religious architecture, but also on its artisans, patrons, resources and intentions. Most of the ecclesiastical buildings show how builders and reused materials were the main protagonists in the building project, not architects, stonemasons and quarried material. All these aspects are the main indicator of change.
Regarding building material, roughly cut stone, obtained from abandoned ancient quarries or from superficial exploitations, was employed to build up walls. Irregular courses and joints were due to the lack of any accurate selection of material before setting, to a limited working of the stone and to the use of basic working tools. More regular stones, almost always reused Roman ones, were only employed to construct structural elements, such as jambs, lintels and quoins, all of them requiring hardly any recutting for their respective new purposes. This shows that quarries were no longer exploited in large scale and that stonemasons were not that common.
Reused Roman materials were regularly employed both for supports – not only for walls as mentioned above – and for architectural sculpture, including liturgical elements.[12] Columns and bases were systematically obtained from Roman constructions, mostly with capitals, although the latter were also newly produced. All these elements entail a double value: first, most of them were of marble, material which was not being exploited at that time and was therefore much appreciated; and second, they were already elaborated, requiring only small adaptations to be re-fitted. There was no other way of obtaining marble (and therefore columns) than plundering. It was common besides to find single elements reemployed in other functions (e.g. capitals reused as masonry in the walls or upside-down as bases, epigraphs reused as imposts, etc.). This proves that these pieces had lost their original purposes and that this practice of material recycling was simply a way of employing available material, not recovering a real or imagined Roman heritage.[13]
These composite constructions were simple in structural terms. Although no standing vaults are extant, reused Roman bricks and rough stone masonry have been recorded by means of the excavations of the apses or sanctuaries. Halls were timber roofed, but not vaulted, as it is shown by the design of the plans (single and long spaces, frequently wide) and the lack of further reinforcements (e.g. external buttresses, transversal arches). Although many of these ecclesiastical constructions witnessed further modifications during the Visigothic period, they mostly kept their original outline, either basilical or single nave, not requiring additional reinforcements and showing thus that structural knowledge was not improved during these centuries. The simplicity of construction entailed also a minimization of auxiliary building devices (such as scaffoldings and timber frames), which made it possible to economize on construction expenses. This saving has to be considered as well with that of the plundered but not quarried material.
Within this context, sculptural production seems to be the only specialized task, representing the elements rarely worked on site (e.g. Tolmo de Minateda).[14] Its working traces show how they were produced far from the building site, probably in workshops located at urban areas (Merida, Toledo or Cordoba, for instance); once on site, these elements frequently required reworking before they could be set in the construction. This shows how little coordination there was between builders on site and sculptors off site. However, this hypothesis needs geological (and petrological) exams of the sculptured stone material to be firmly confirmed.
Finally, working instruments both for construction and sculpture were fewer and simpler than in previous and later periods. Roman drilling is not recorded in architectural sculpture, for instance, and set-square is not used either when designing the regular stone walls.[15] This short diversity of working tools explains the aforementioned irregularity of stone courses in walls and is related as well to the availability of metal (necessary to produce quarrying instruments, among others), the cycle of production of which also decreased in late antiquity.[16]
Artisans and Identity
Collectively, these features, representing late antique building technology, should not be seen singularly as a sign of decay, but rather as an indicator of social and economic change coinciding with modifications to the general organization of manufacturing. The complexity of the production activities (the cycle of production of stone, of brick, of metal, of timber, etc.) decreased after the Roman Empire, which is especially true of duties that required specific technical skills, such as shaft cutting and stonemasonry. Structural knowledge, that is, the capacity to plan construction projects and to overcome technical problems and engineering issues,[17] was less necessary and so with it also the architect. All in all, there was a reduction in the division of labor and specialization because of a lack of demand, which should be associated directly with the simplification of the Visigothic social structure.[18]
Related to this, the analysis of those scarce late antique written records proves how the term architectus becomes less common during this period, progressively substituted by others terms. This does not mean that architects, in the classical sense of an educated artisan with social and economic status, disappeared.[19] Isidore of Seville illustrates this when indicating that the architect’s task is the disposition of the foundations, that is, the design of the ground-plan, but neither the construction nor the embellishment of the building.[20] Isidore considered architects as special builders, not as highly qualified workers. Complementing the archaeological evidence, it is possible then to say that this change entailed two further alterations regarding the identity of architects/masons in the late antiquity.
Firstly, the difference between architects and builders was vague, since architects were distinguished by manual knowledge, not theoretical. The absence of architectural treatises might reflect that craftsmen were not sufficiently educated and too self-conscious about their work to write about it, since Isidore (a cleric) was the only reference to them in this period. All craftsmen seem to have been masons, some more qualified than others due to previous experience, not theoretical education. Furthermore, apart from working spaces probably situated in urban areas and devoted to sculptural production and the temporary spaces on construction sites themselves, there were probably no spaces dedicated to architectural planning. This is an important issue since, in later periods, mainly from the late medieval periods onwards, there was a spatial construction of artisanal identity thanks to the establishment of permanent working areas.
Secondly, unlike in the Roman and Late Medieval periods, architects were no longer distinguished in terms of social and economic status. Education was part of that social status, but also visibility and salaries.[21] Neither is a single late antique or early medieval building artisan known of by means of written records – except for founders and bishops (these mainly as consecrators)[22] – nor are there any extant building contracts that could allow us to delve deeper into the identities of builders.
The construction of buildings was, by far, the most expensive endeavor at that time (and nowadays), and was, as such, extremely dependent on patronage relations. Since most of the ecclesiastical buildings were commissioned by laymen (and consecrated by bishops), it seems that workers were economically dependent on the aristocracy. The importance of aristocratic individuals and families, also attested by the epigraphic records especially in the rural areas,[23] as providers of funds, as contractors for buildings, and presumably as instigators of them, was fundamental, so artisans responsible for construction must have rather dealt with the individual or family concerned than with the state or the ecclesiastical authority. It is probable then that workers developed other activities coevally and related to these families. If so, this would be a clear break between the Roman period, in which the state was the greatest commissioner, and early medieval society, in which monastic communities were the primary motivator of building projects.
Monumental architecture and monumental architects gave way consequently in late antiquity to humble constructions and humble craftsmen trained in traditional skills, dependent on aristocracy, but lacking further theoretical and complex structural knowledge and material resources (mainly those of new origin). This therefore makes it hard for scholars to speak of the existence in Visigothic Iberia of an artisanal community as a communal craft group, as will develop in later periods.
NOTES
[1] Tenured Researcher, Escuela de Estudios Árabes (EEA)-Consejo Superior de Investigaciones Científicas (CSIC), Cuesta del Chapiz 22, Granada 18010, Spain, mariaangeles.utrero@eea.csic.es.
[2] Isaac Sastre and María de los Ángeles Utrero, “Tracing influences in Mozarabic Material Culture: Building Technology in 8-10th century Hispanic Churches,” in The Late Antique World of Early Islam: Muslims among Christians and Jews in the East Mediterranean, ed. Robert Hoyland (Princeton: The Darwin Press, 2015), 195-229.
[3] On technology and ways of transferring it see María de los Ángeles Utrero, “Modelos arquitectónicos y decorativos a inicios del siglo X. Algunas certezas y varias hipótesis,” Arqueología y Territorio Medieval 24 (2017): 185-206.
[4] This classification and terminology has changed little since the earliest studies of early medieval Hispanic architecture, and has been commonly accepted. María de los Ángeles Utrero, Iglesias tardoantiguas y altomedievales en la Península Ibérica. Análisis arqueológico y sistemas de abovedamiento (Madrid: CSIC, 2006), 25-45.
[5] For the chronology and geography of the Byzantine occupation see Sebastián Ramallo and Jaime Vizcaíno, “Bizantinos en Hispania. Un problema recurrente en la arqueología española,” Archivo Español de Arqueología 75 (2002): 313-32.
[6] Luis Caballero, “Un canal de transmisión de lo clásico en la Alta Edad Media Española. Arquitectura y Escultura de influjo omeya en la Península Ibérica entre mediados del siglo VIII e inicios del siglo X,” Al-Qantara XV/2 (1994-1995), 321-348 and XVI/1, 107-24.
[7] The chronology of the second half of the seventh century for this group of buildings was primarily based on epigraphic sources and stylistic and comparative arguments, since most of them had either not been excavated (e.g. Santa Comba de Bande, San Pedro de la Mata, San Pedro de la Nave) or the excavations had not been carried out in accordance with stratigraphic principles (e.g. San Juan de Baños, Quintanilla de las Viñas). All of them can be found in Utrero, Iglesias tardoantiguas y altomedievales en la Península Ibérica.
[8] For an overview of current views on both models and their evolution see Sastre and Utrero, “Tracing influences in Mozarabic Material Culture.”
[9] John Bryan Ward-Perkins: “Quarries and stoneworking in the Early Middle Ages: the heritage of the Ancient World,” in Settimane di Studio del Centro Italiano di studi sull’alto medioevo XVIII (Spoleto: CISAM, 1971), 525-44. Archaeological research in important Hispanic cities such as Toledo, Reccopolis (thought to have been founded in 578 [on both see Lauro Olmo, “Ciudad y Estado en época visigoda: Toledo, la construcción de un nuevo espacio urbano,” in Espacios urbanos en el Occidente mediterráneo (s. VI-VIII) [Toledo: Toletvum Visigodo, 2010], 87-111) or Mérida (Miguel Alba, “Diacronía de la vivienda señorial de Emerita (Lusitania, Hispania): desde las domus alto imperiales y tardoantiguas a las residencias palaciales omeyas (siglos I-IX),” in Archeologia e Società tra tardo antico e alto medioevo, ed. Gian Petro Brogiolo and Alexandra Chavarría [Mantua: SAP, 2007], 163-92) has not hitherto uncovered any remains of monumental architecture built in ashlar stone masonry and attributed to the sixth and seventh centuries.
[10] While late antique buildings seem to have been built using recycled material, due to a lack of available new supplies, those buildings which date from the late eighth century onwards appear to have been constructed with both old and new material. On this phenomenon see María de los Ángeles Utrero and Isaac Sastre, “Reutilizando materiales en las construcciones de los siglos VII-X. ¿Una posibilidad o una necesidad?,” Anales de Historia del Arte 22, Nº Esp. II (2012), 309-23.
[11] Among others: Pedro Mateos, La basílica de Santa Eulalia de Mérida. Arqueología y urbanismo (Madrid: CSIC, 1999); Sonia Gutiérrez Lloret and Pablos Cánovas, “Construyendo el siglo VII: arquitecturas y sistemas constructivos en El Tolmo de Minateda,” in El siglo VII frente al siglo VII. Arquitectura, ed. Luis Caballero, Pedro Mateos and María de los Ángeles Utrero (Madrid: CSIC, 2009), 91-132; Sonia Gutiérrez Lloret, “La iglesia altomedieval de la Silla del Papa (Tarifa, Cádiz),” Mélanges de la Casa de Velázquez N.S. 47-1 (2017): 201-14; Luis Caballero and Fernando Sáez, “La iglesia de El Gatillo de Arriba (Cáceres). Apuntes sobre una iglesia rural en los siglos VI al VIII,’ in El siglo VII frente al siglo VII, 155-84; María de los Ángeles Utrero, “Estratigrafía, epigrafía y escultura reutilizada en la basílica de Segóbriga. Nuevos datos para su interpretación,” Anales de Prehistoria y Arqueología de la Univ. de Murcia 30 (2014): 157-77; Tomás Cordero and Isaac Sastre, “El yacimiento de Casa Herrera en el contexto del territorio emeritense (siglos IV-VIII),” in Espacios urbanos en el occidente mediterráneo, 211-18; and, María de los Ángeles Utrero and Francisco José Moreno, “Evergetism among the bishops of Hispania between the sixth and seventh centuries: a dialogue between archaeological and documentary sources,” Journal of Early Christian Studies 23.1 (2015): 97-131, with further references.
[12] Utrero and Sastre, “Reutilizando materiales en las construcciones de los siglos VII-X.” Isaac Sastre, Los altares de las iglesias hispanas tardoantiguas y altomedievales. Estudio arqueológico (Oxford: Archaeopress, 2013).
[13] Dale Kinney, “Roman Architectural Spolia,” Proceedings of the American Philosophical Society 145-2 (2001): 138-50.
[14] Gutiérrez Lloret and Cánovas, “Construyendo el siglo VII.”
[15] According to Jean-Claude Bessac (La Pierre en Gaule Narbonnaise et les carrières du bois des Lens (Nîmes). Histoire, archéologie, ethnographie et techniques, Journal of Roman Archaeology 16, Supplement [1996]), available instruments at the quarry were also less in number and variety, which partially explains the irregularity of the exploitations. This affirmation is based on his study of late antique and early medieval quarries in France, but this is unknown for the Iberian Peninsula, since quarries have not been yet properly studied.
[16] Bessac, La Pierre en Gaule Narbonnaise et les carrières du bois des Lens (Nîmes).
[17] Kenneth Douglas White, Greek and Roman Technology (Ithaca: Cornell University Press, 1984), 73.
[18] On this see Damián Fernández (“Property, Social Status, and Church Building in Visigothic Iberia,” Journal of Late Antiquity 9.2 [2016]: 512-41), who convincingly defends the argument that church-building, especially in rural areas, was a mark of high social standing for those who commissioned the construction.
[19] Nikolaus Pevsner, “The term Architect in the Middle Ages,” Speculum 17 (1942): 549-62; Spiro Kostof, “El arquitecto en la Edad Media, en Oriente y Occidente,” in El Arquitecto. Historia de una profesión, ed. Spiro Kostof (Madrid: Cátedra, 1984 [1st ed. New York, 1977]), 65-97.
[20] Isidore, Etymologies, XIX.8: “Architecti autem caementarii sunt, qui disponunt in fundamentis.”
[21] Mark Wilson Jones (Principles of Roman Architecture [New Haven: Yale University Press, 2000], 28) mentions how rules established a larger economic benefit for the Roman architect. Also, Peter Stewart, The Social History of Roman Art (Cambridge: Cambridge University Press, 2008), 24. For the late medieval period see Beatriz Mariño, “La imagen del arquitecto en la Edad Media: historia de un ascenso,” Espacio, Tiempo y Forma VII-13 (2000): 11-25. This is a less-studied aspect of the Early Middle Ages, due to a lack of complementary written records (see María de los Ángeles Utrero, “Modelos arquitectónicos y decorativos a inicios del siglo X.”)
[22] Utrero and Moreno, “Evergetism among the bishops of Hispania.”
[23] Idem.
Bibliography
Primary
Isidore of Seville. Etymologies. Isidori Hispalensis Episcopi Etymologiarum sive Originum Libri XX. Edited by W. M. Lindsay. Oxford: Oxford University Press, 1911; The Etymologies of Isidore of Seville, trans. by Stephen A. Barney, W. J. Lewish, J. A Beach and Oliver Berghof. Cambridge: Cambridge University Press, 2006.
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Alba, Miguel. “Diacronía de la vivienda señorial de Emerita (Lusitania, Hispania): desde las domus alto imperiales y tardoantiguas a las residencias palaciales omeyas (siglos I-IX),” In Archeologia e Società tra tardo antico e alto medioevo, edited by Gian Pietro Brogiolo and Alexandra Chavarría, 163-92. Mantua: SAP, 2007.
Bessac, Jean-Claude. La Pierre en Gaule Narbonnaise et les carrières du bois des Lens (Nîmes). Histoire, archéologie, ethnographie et techniques, Journal of Roman Archaeology 16, Supplement, 1996.
Caballero, Luis. “Un canal de transmisión de lo clásico en la Alta Edad Media Española. Arquitectura y Escultura de influjo omeya en la Península Ibérica entre mediados del siglo VIII e inicios del siglo X.” Al-Qantara XV/2 (1994-95): 321-348 and XVI/1, 107-24.
Caballero, Luis and Fernando Sáez. “La iglesia de El Gatillo de Arriba (Cáceres). Apuntes sobre una iglesia rural en los siglos VI al VIII.” In El siglo VII frente al siglo VII. Arquitectura, edited by Luis Caballero, Pedro Mateos and María de los Ángeles Utrero, 155-84. Madrid: CSIC, 2009.
Cordero, Tomás and Isaac Sastre. “El yacimiento de Casa Herrera en el contexto del territorio emeritense (siglos IV-VIII).” In Espacios urbanos en el occidente mediterráneo (s. VI-VIII), edited by Alfonso García, 211-18. Toledo: Toletvum Visigodo, 2010.
Fernández, Damián. “Property, Social Status, and Church Building in Visigothic Iberia.” Journal of Late Antiquity 9.2 (2016): 512-41.
Gutiérrez Lloret, Sonia. “La iglesia altomedieval de la Silla del Papa (Tarifa, Cádiz).” Mélanges de la Casa de Velázquez N.S. 47-1 (2017): 201-14.
Gutiérrez Lloret, Sonia and Pablo Cánovas. “Construyendo el siglo VII: arquitecturas y sistemas constructivos en El Tolmo de Minateda.” In El siglo VII frente al siglo VII. Arquitectura, edited by Luis Caballero, Pedro Mateos and María de los Ángeles Utrero, 91-132. Madrid: CSIC, 2009.
Jones, Mark Wilson. Principles of Roman Architecture. New Haven: Yale University Press, 2000.
Kinney, Dale. “Roman Architectural Spolia.” Proceedings of the American Philosophical Society 145-2 (2001): 138-50.
Kostof, Spiro. “El arquitecto en la Edad Media, en Oriente y Occidente.” In El Arquitecto. Historia de una profesión, edited by Spiro Kostof, 65-97. Madrid: Cátedra, 1984 (1st edn. New York, 1977).
Mariño, Beatriz. “La imagen del arquitecto en la Edad Media: historia de un ascenso.” Espacio, Tiempo y Forma VII-13 (2000): 11-25.
Mateos, Pedro. La basílica de Santa Eulalia de Mérida. Arqueología y urbanismo, Madrid: CSIC, 1999.
Olmo, Lauro. “Ciudad y Estado en época visigoda: Toledo, la construcción de un nuevo espacio urbano.” In Espacios urbanos en el occidente mediterráneo (s. VI-VIII), edited by Alfonso García, 87-111. Toledo: Toletvum Visigodo, 2010.
Pevsner, Nikolaus. “The term Architect in the Middle Ages.” Speculum 17 (1942): 549-62.
Ramallo, Sebastián and Jaime Vizcaíno. “Bizantinos en Hispania. Un problema recurrente en la arqueología española.” Archivo Español de Arqueología 75 (2002): 313-32.
Sastre, Isaac. Los altares de las iglesias hispanas tardoantiguas y altomedievales. Estudio arqueológico. Oxford: Archaeopress, 2013.
Sastre, Isaac and María de los Ángeles Utrero. “Tracing influences in Mozarabic Material Culture. Building Technology in 8-10th century Hispanic Churches.” In The Late Antique World of Early Islam: Muslims among Christians and Jews in the East Mediterranean, edited by Robert G. Hoyland, 195-229. Princeton: The Darwin Press, 2015.
Stewart, Peter. The Social History of Roman Art. Cambridge: Cambridge University Press, 2008.
Utrero, María de los Ángeles. Iglesias tardoantiguas y altomedievales en la Península Ibérica. Análisis arqueológico y sistemas de abovedamiento. Madrid: CSIC, 2006.
Utrero, María de los Ángeles. “Estratigrafía, epigrafía y escultura reutilizada en la basílica de Segóbriga. Nuevos datos para su interpretación.” Anales de Prehistoria y Arqueología de la Univ. de Murcia 30 (2014): 157-77.
Utrero, María de los Ángeles. “Modelos arquitectónicos y decorativos a inicios del siglo X. Algunas certezas y varias hipótesis.” Arqueología y Territorio Medieval 24 (2017): 185-206.
Utrero, María de los Ángeles and Francisco José Moreno. “Evergetism among the bishops of Hispania between the sixth and seventh centuries: a dialogue between archaeological and documentary sources.” Journal of Early Christian Studies 23.1 (2015): 97-131.
Utrero, María de los Ángeles and Isaac Sastre. “Reutilizando materiales en las construcciones de los siglos VII-X. ¿Una posibilidad o una necesidad?” Anales de Historia del Arte 22, Nº Esp. II (2012): 309-23.
Ward-Perkins, John Bryan. “Quarries and stoneworking in the Early Middle Ages: the heritage of the Ancient World.” In Settimane di Studio del Centro Italiano di studi sull’alto medioevo XVIII, 525-44. Spoleto: Centro Italiano di Studi sull’Alto Medievo, 1971.
White, Kenneth Douglas. Greek and Roman Technology. Ithaca: Cornell University Press, 1984.
Visigothic Symposia 