ROSONE. – A circular window decorated with tracery, generally situated on the front of churches.
The use of strongly splayed circular openings, called “oculi,” in the sides and apses of churches is already noted in the Carolingian period; but only at the beginning of the twelfth century were they adopted on the façades of northern Italy together with large mullioned or single-light windows, so that their importance remained secondary, both compositionally and for purposes of illumination (S. Michele Maggiore, S. Pietro in Ciel d’Oro in Pavia, the cathedral of Chieri). In the second half of the same century, the type of the r. with a radial arrangement of small columns began to take shape; its first example is perhaps that of S. Maria Maggiore in Assisi, whose frame bears the date 1162, slightly earlier than those of the Cistercian churches (Fossanova, Casamari, Valvisciolo, Chiaravalle della Colomba), in which the r. constitutes one of the characteristic elements of the façade. This type continued at the beginning of the thirteenth century, at times inserted into the lunette of the portal (lower basilica of S. Francesco in Assisi) or structurally and decoratively connected with the large window (abbey church of S. Martino al Cimino), and retained the original form with a single ring of small columns. In the Apulian cathedrals, the dimensions increased considerably, while the decoration introduced the motif of interlaced arches (Troia, Altamura) or trefoils (Ruvo); the frames likewise became richer through the addition of decorative elements (cathedral of Bari). At times the r. is contained within a large relieving arch with the archivolts left visible, thereby combining a decorative function with a structural one (cathedrals of Bovino and Troia); this system is unquestionably of French derivation.
But already in the first half of the century, especially in churches, the primitive form also became more complex; the number of rings of small columns increased, often with spiral shafts, and the decorative motifs became more elaborate, with recurring circles and multilobes, while the symbols of the Evangelists were placed on the exterior to form a framing device (upper basilica of S. Francesco in Assisi, S. Pietro and S. Maria Maggiore of Tuscania, cathedrals of Assisi, Foligno, and Spoleto). Likewise, in churches with several portals it was common to surmount each of them with an r., generally with the central one larger and placed higher (S. Pietro of Assisi, the cathedrals of Assisi and Foligno, already mentioned, and those of S. Miniato, Volterra, and Todi); characteristic is the cathedral of Spoleto, on whose façade, beside the principal r., two smaller ones open, with three others along the slopes of the gable. This element also spread to northern Italy, not only in Cistercian churches (S. Andrea of Vercelli), but also in others, attaining large dimensions, though always with a simple ring of small columns (cathedral of Modena, cathedral and S. Antonino of Piacenza), at times paired in certain Veronese churches (S. Fermo Maggiore, S. Zeno). Also characteristic is the superimposition of r.s on the same vertical axis of the façade (S. Paolo of Pistoia), as well as their adoption in apses and transepts (S. Andrea of Vercelli, cathedral of Piacenza). This spread and increase in dimensions were influenced by the general tendency of Gothic architecture to increase window surfaces in order to reduce the masonry of the walls to the mere load-bearing framework. This occurred particularly in France, where the r. then acquired the status of a dominant element in the architectural organization of the façade: the cathedrals of Poitiers, Carcassonne, Chartres, St-Remy, Amiens, and Orléans, and Notre-Dame of Paris.
The fourteenth century generally continued the forms and arrangements of the preceding century, with greater elegance in the almost carved tracery and a preference for the multilobed arches characteristic of Flamboyant Gothic. Thus, at S. Maria di Collemaggio in L’Aquila and in the cathedral of Cremona, the three r.s appear on the façade, with the central one richer, having multiple rings in the former church and a single ring in the latter; in the cathedrals of Lanciano and Bitetto, the r. is inserted into a large arch with strongly projecting frames and supported by piers. The arrangement in the cathedral of Teramo is singular, with the r. inserted into the cusp of the portal. A particular arrangement found in certain Umbrian and Tuscan churches (S. Caterina of Pisa, the cathedrals of Orvieto and Carrara) is that of the r. inscribed within a square decorated with panels and with fully relief-carved figures of saints or symbols at the corners; apart from this last motif, the same arrangement is also found in the Collegiata of Monza.
In the fifteenth century the use of the r. became more sporadic in Italy, persisting above all in Abruzzo, where the Gothic tradition survived longer (S. Maria Assunta of Assergi, S. Maria della Tomba at Sulmona, S. Lucia at Magliano dei Marsi), while in the other regions it had become almost exceptional (S. Luca of Cremona, Colleoni Chapel of Bergamo); it then almost entirely disappeared in the second half of the century with the decisive predominance of Renaissance forms, which replaced it with a simple oculus with a frame. Perhaps the latest expression is found in S. Maria dei Miracoli in Venice (1483), where the motif of the inner circle and the two interlaced crosses reveals a calmer rhythm in comparison with the whirling decorative style of the Gothic.
The Palazzo comunale of Piacenza may be recalled as an entirely exceptional case, perhaps the only example of the adoption of the r. in civil architecture. – Vedi tav. LXXXIV.