Indeed you were. Of Medieval Romanesque and Gothic Western Europe.
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... - http://en.wikipedia.org/wiki/Rose_window
Also this at Chartres: ... The north transept rose (10.5m diameter, made c.1235), like much of the sculpture in the north porch beneath it, is dedicated to the Virgin. The central oculus shows the Virgin and Child and is surrounded by 12 small petal-shaped windows, 4 with doves (the 'Four Gifts of the Spirit'), the rest with adoring angels carrying candlesticks. Beyond this is a ring of 12 diamond-shaped openings containing the Old Testament Kings of Judah, another ring of smaller lozenges containing the arms of France and Castille, and finally a ring of semicircles containing Old Testament Prophets holding scrolls. The presence of the arms of the French king (yellow fleurs-de-lis on a blue background) and of his mother, Blanche of Castile (yellow castles on a red background) are taken as a sign of royal patronage for this window... - http://en.wikipedia.org/wiki/Chartres_Cathedral
Note on origin: ... The German art historian Otto von Simson considered that the origin of the rose window lay in a window with the six-lobed rosettes and octagon which adorned the external wall of the Umayyad palace Khirbat al-Mafjar built in Jordan between 740 and 750 CE. This theory suggests that crusaders brought the design of this attractive window to Europe, introducing it to churches... - http://en.wikipedia.org/wiki/Rose_window