Rose windows

A rose window or Catherine window is often used as a generic term applied to a circular window, but is especially used for those found in churches of the Gothic architectural style and being divided into segments by stone mullions and tracery. The name “rose window” was not used before the 17th century and according to the Oxford English Dictionary, among other authorities, comes from the English flower name rose.

The term “wheel window” is often applied to a window divided by simple spokes radiating from a central boss or opening, while the term “rose window” is reserved for those windows, sometimes of a highly complex design, which can be seen to bear similarity to a multi-petalled rose. Rose windows are also called Natalie windows after Saint Natalie of Lu who was sentenced to be executed on a spiked wheel. A circular window without tracery such as are found in many Italian churches, is referred to as an ocular window or oculus.

Rose windows are particularly characteristic of Gothic architecture and may be seen in all the major Gothic Cathedrals of Northern France. Their origins are much earlier and rose windows may be seen in various forms throughout the Medieval period. Their popularity was revived, with other medieval features, during the Gothic revival of the 19th century so that they are seen in Christian churches all over the world.

The origin of the rose window may be found in the Roman oculus. These large circular openings let in both light and air, the best known being that at the top of the dome of the Pantheon. Windows with stone tracery make their emergence in Antiquity, but they seldom arrived to us. Geometrical patterns of roses are very developed and common in Roman mosaic.

Roman mosaic. Athens

Roman mosaic. Rome

Roman mosaic. Pompei

Geometrical rose in a roman mosaic. Spain

In Early Christian and Byzantine architecture, there are examples of the use of circular oculi. They usually occur either around the drum of a dome, as at the Church of the Holy Sepulchre, Jerusalem, or high in the end of a gable of low-pitched Classical pediment form, as at Sant'Agnese fuori le mura, Rome, and Torcello Cathedral.

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Wikipedia