The interest of researchers for mural painting in Portugal is relatively recent. It began with Virgílio Correia, in 1921, when he first attempted to create a scientific discussion around this topic, proposing methodological criteria to the analysis of mural paintings. Electing the 15th and the 16th centuries as the 'golden period' of Portuguese mural painting, this art historian examined several sets of paintings from the stylistic point of view, proposing authorships which he sought to support through documentary sources. Despite all the difficulties existing at the time to carry out a rigorous analytical work, Virgílio Correia was the first to suggest that easel painters might have been involved also in wall assemblies. At the same time, all stylistic comparisons made by the author were based on the paradigm of the Italian wall painting – the 'buon fresco' - and its excellence, which would eventually create a wrong image of the Portuguese pictorial reality shared, by other authors, at least until the first half of the 20th century.
Between 1930 and 1940, the Portuguese State carried out an intense campaign of restoration works on murals sets of the country’s northern region, where older examples had been identified. Interventions followed the criterion of 'unity of style' and led to formal amendments and materials in many paintings as opposed to southern Portugal where the 'whitewash ideology' ruled over the built heritage sparing a significant collection of specimens and allowed them to arrive unchanged to this day.
Between 1930 and 1940, the Portuguese State carried out an intense campaign of restoration works on murals sets of the country’s northern region, where older examples had been identified. Interventions followed the criterion of 'unity of style' and led to formal amendments and materials in many paintings as opposed to southern Portugal where the 'whitewash ideology' ruled over the built heritage sparing a significant collection of specimens and allowed them to arrive unchanged to this day.
The mural historiography would have, however, to wait till the 80's when art historians intensified their studies devoted to mural painting, focusing on the transition period from the late Gothic to the early Renaissance, particularly in the north. In 1982 the inventory led by Teresa Cabrita Fernandes constitutes a pioneering work that opened the way to a new historiographical current. Later on, the studies of Catarina Valença developed the theme of mural painting, in what were its main features and characteristics, in the municipality of Alvito (Alentejo) and several other locations in the Castelo Branco District.
Mural painting was further analysed in a broader perspective by Luis Urbano Afonso and Paula Bessa. Focusing on the period between the 15th and 16th centuries, Luis Afonso successfully defined the main characteristics, models and sources of inspiration in mural painting at a national level, in what turned out to be one of the strongest contributions to Late-Medieval Art History. The approach of Paula Bessa was more regionalist, analyzing systematically each core of Late-Gothic paintings in the north of Portugal. More recently, Joaquim Inácio Caetano conducted a systematic survey of the models used in stencils in decorative motifs of the compositions of the 15th and 16th centuries. This work has given, thus, more consistency to the knowledge about the Northern mural paintings. Simultaneously the same author dedicated himself to the theme of the fake masonry and all the techniques referring to the artistic treatment of the stone joints, an area of great abundance of cases, though not always considered by the Portuguese Art historiography.
All these authors have contributed to the knowledge about mural painting of the north and centre of the country, defining characteristics, workshops and identifying models (from the Hispano-Flemish models to the Renaissance language).
With regard to, specifically, Alentejo, we find that there are two main poles around which researchers from Portuguese mural concentrated their attention.
First, the city of Évora and its surrounding region, for the political and cultural importance which represented during the periods in which the court had been installed there, especially during the reign of King Manuel (1495-1521), then King John III (1521-1557) and all the artistic repercussions from there to the nearby municipalities.
Joaquim Oliveira Caetano and José Alberto Carvalho Seabra studied some of the 16th century Évora examples, of a higher artistic and iconographic richness. Two examples of high quality fresco paintings are the Palace of the Counts of Basto and the famous Painted Houses of Vasco da Gama, with its unusual iconography spread through medieval books of fables. Also worth mentioning the survey carried out by Margaret Donas Botto also around the municipality of Évora, on the aspects related to the self-preservation of the still remaining ensembles, all of them belonging to the modern period. The work of Celina Simas Oliveira regarding the New Sacristy of the Colégio do Espírito Santo in Évora also reflects the same concern regarding the study and analysis of the causes of mural degradation. In 2014, this case was revisited by team members in task 2 which resulted in a exhaustive assessment of its pictorial technique and current condition (scientific report in unpublished documentation). The complementarities between the historical study and the examination and diagnosis had already been tested in another case study, not so well known, although older - the fresco of the former Court of Monsaraz – restored by Teresa Sarsfield Cabral and Irene Frazão (1999).
Gradually, the biographies of painters are being built up, outlining their geographical areas of action and collaborators. Within this context, the studies of Vitor Serrão about the rehabilitation of the Portuguese Renaissance and Manneirist frescoeshave also been vital. One of this author’s most relevant studies is dedicated to the fresco of the Ermida de Santo Aleixo (Montemor-o-Novo), a true 'masterpiece of the Portuguese Renaissance', which continues to raise questions in terms of authorship. For the Montemor-o-Novo county and especially its mural painting heritage, the inventory study by Nelson Dias must be considered.
The region around Vila Viçosa was also the target of several studies of Vitor Serrão, due to its role as a centre of dynamic artistic activities in the neighbouring areas. Vila Viçosa, a true 'village court' whose cultural and artistic revival was due to the Braganza family, offers a bright chapter in the history of the national fresco, in what concerns the complex, intellectualized and humanistic periods of the Renaissance and Mannerism. On the other side of the spectre are the pictorial sets attributed to the workshop of José de Escovar, paradigmatic figure of the fresco technique of the late 16th and early 17th centuries, much rehabilitated at the present thanks to studies that have been dedicated to him by the same author (Fig.3)Within a more regional perspective, it was performed a study on the counties of Estremoz, Borba, Vila Viçosa and Alandroal (together designated as the 'Marble Region'), for the second half of the 17th and 18th centuries.
The paintings of this period had not until then been subject to any broader historical and artistic study, so this essay is the first to bring novelties on a documentary and iconographic point of view, proposing new readings for assemblies analyzed.
The second pole was the southern region of Évora, which mostly belongs to the Beja District and that was also the focus of several studies. Here it should be recalled, once again, the work of Catarina Valença in the study and, above all, the dissemination of knowledge about Alentejo frescoes to the different audiences, contributing to their rehabilitation, which, in some cases, resulted in fruitful interventions of conservation and restoration.
Thus, gradually, the historiography of the mural painting was being built, being undeniable the researchers growing interest for the historical period covering the end of the Gothic and the beginning of Renaissance, perhaps because of the rarity and even the quality of many of pictorial sets of this phase.
On the other hand, the correct definition of what was, actually, the beginning of our mural painting came to overthrow some ideas that became questionable, particularly the belief in the 'decline' of the fresco since the second half of the 16th century. As well underlined by Luís Afonso, this theory could have been related to '[...] the absence of a credible 'corpus' of late medieval easel painting. Therefore, the most studied murals were precisely the oldest, which is to say, in our case, to painting produced in Portugal during the reign of King Manuel and the beginning of the reign of King John III [...]'.
Simultaneously, mural painting has been the subject of technical and/or scientific PhD researches that approached the theme starting from its constituent materials and pictorial technologies. Within this perspective, we highlight the essays by Milene Gil and Joaquim Inácio Caetano as two of the most recent contributions to this issue. Milene Gil’s dissertation sought to address the entire process of coloured whitewash on the Alentejo’s façades, using different scientific methods of examination and analysis (fluorescence spectrometry X-rays, particle size analysis of pigments, etc.). The researcher conducted a detailed study of the materiality of the Alentejo mural painting thus continuing the work started by other authors such as José Aguiar . Also in the subject of the mural and architectural coatings we must underline Joaquim Inácio Caetano’s PhD dissertation, where the author made a considerable survey of the stamp motifs used in easel painting, defining thereby workshop production methods during the 15th and 16th centuries. He also addressed the issue of the fake masonries and joint treatments in buildings, both within their decorative and protective components. In May 2013, Patricia Monteiro presented her PhD dissertation on mural painting in the Northern Alentejo region, also looking to integrate this area in the State of the Art of this theme, calling attention to a virtually unknown endangered heritage.