The research on one of the best-preserved medieval ensembles in the country, in the monastery of Oña (Burgos), reaffirms polychromy as an indispensable element in church decoration. 

Visitors to the ancient chapter house of San Salvador de Oña, a monastery established in the early 11th century in northern Burgos, encounter the remains of several polychrome Romanesque arches over 800 years old. Art historian Ana María Cuesta, who has spent the last decade studying the understanding of color in medieval Europe, acknowledges that while the site is exceptional, viewers often leave without fully appreciating what they’ve seen. She argues that color had much more significance in the past, and a sculpture was not considered complete unless it was polychrome. Today’s society tends to favor the immaculate image of bare stone seen in most religious temples, which is a stark contrast to the colorful reality of the Middle Ages. Misconceptions perpetuated by 19th–century literature and cinema have tarnished the true vibrant image of the medieval era. Cuesta points out the rich chromaticity of the Oña arches and other notable examples, such as the Portico of the Majesty of Toro Collegiate Church. Artists began to distrust medieval colors and gilding from the mid–15th century, with the advent of the Renaissance favoring the «ideal beauty‘ of Greek and Roman art and the seductive power of ‘nudes made in white marble‘. This approach was misleading, as over time, classical marbles lost their original abundant polychromy due to burial or weathering. Cuesta reveals that polychromy and painting were not only used for aesthetic enhancement of sculptures and narrative portals but also to cover all types of surfaces, protecting stone from moisture, wear, or use. However, when the vibrant tones of the Middle Ages fell out of fashion, colors ended up hidden under successive whitewashings. Aggressive restorations in the 19th century stripped away these layers, including the original medieval colors, leaving very few intact examples. Art historian and restorer Carlos Nodal highlights the use of precious materials like gold and lapis lazuli, an intense blue gem imported from the Near East. Cuesta has also found a significant presence of decorative metals in San Salvador de Oña, a practice more common in Italy or France. Cuesta insists on the protective and aesthetic function of pigments in the ‘dark‘ Middle Ages and the non–exclusive symbolism of color. Each color tone had a specific meaning, for instance, bright yellow could signify divinity, while a duller yellow represented the presence of the devil. Nodal, however, argues for a general symbolism to ‘draw attention‘ and as a display of wealth by the royals or the Church. The ignorance of color’s crucial role in the Middle Ages has led to the destruction of many of its testimonies. Cuesta calls for a careful restoration of the San Salvador de Oña arches, considering them to be delicate pieces worthy of in–depth study.