The development of secular vernacular literature focusing on human concerns did not mean any lessening of the importance of religion in medieval people’s lives. As we have seen, religious devotion was expressed through daily rituals, holiday ceremonies, and the creation of new institutions such as universities and religious orders. People also wanted permanent visible representations of their piety, and both church and city leaders wanted physical symbols of their wealth and power. These aims found their outlet in the building of tens of thousands of churches, chapels, abbeys, and, most spectacularly, cathedrals in the twelfth and thirteenth centuries. A cathedral is the church of a bishop and the administrative headquarters of a diocese. The word comes from the Greek word kathedra, meaning seat, because the bishop’s throne, a symbol of the office, is located in the cathedral.

Most of the churches in the early Middle Ages had been built primarily of wood, which meant they were susceptible to fire. They were often small, with a flat roof, in a rectangular form with a central aisle; this structure, called a basilica, was based on earlier Roman public buildings. With the increasing political stability of the eleventh century, bishops and abbots supported the construction of larger and more fire-resistant churches made almost completely out of stone. As the size of the church grew horizontally, it also grew vertically. Builders adapted Roman-style rounded barrel vaults made of stone for the ceiling; this use of Roman forms led the style to be labeled Romanesque.

The next architectural style was Gothic, so named by later Renaissance architects who thought that only the uncouth Goths could have invented such a disunified style. In Gothic churches the solid stone barrel-vaulted roof was replaced by a roof made of stone ribs with plaster in between. Because this ceiling was much lighter, side pillars and walls did not need to carry as much weight. Exterior arched stone supports called flying buttresses also carried some of the weight of the roof, so solid walls could be replaced by windows, which let in great amounts of light. Originating in the Île-de-France in the twelfth century, Gothic architecture spread throughout France with the expansion of royal power. From France the new style spread to England, Germany, Italy, Spain, and eastern Europe.

Extraordinary amounts of money were needed to build these houses of worship. The economic growth of the period meant that merchants, nobles, and the church could afford the costs of this unparalleled building boom. Moreover, money was not the only need. A great number of artisans had to be assembled: quarrymen, sculptors, stonecutters, masons, mortar makers, carpenters, blacksmiths, glassmakers, roofers. Each master craftsman had apprentices, and unskilled laborers had to be recruited for the heavy work. Bishops and abbots sketched out what they wanted and set general guidelines, but they left practical needs and aesthetic considerations to the master mason. He held overall responsibility for supervision of the project.

Since cathedrals were symbols of civic pride, towns competed to build the largest and most splendid church. In 1163 the citizens of Paris began Notre Dame Cathedral, planning it to reach the height of 114 feet from the floor to the ceiling at the highest point inside. Many other cathedrals well over 100 feet tall on the inside were built as each bishop and town sought to outdo the neighbors. Towers and spires jutted up another several hundred feet. Medieval people built cathedrals to glorify God — and if mortals were impressed, all the better. Construction of a large cathedral was rarely completed in a lifetime; many were never finished at all. Because generation after generation added to the buildings, many of these churches show the architectural influences of two or even three centuries.

Stained glass beautifully reflects the creative energy of the High Middle Ages. It is both an integral part of Gothic architecture and a distinct form of visual art. From large sheets of colored glass made by glassblowers, artisans cut small pieces, linked them together with narrow strips of lead, and set them in an iron frame prepared to fit the window opening. Windows showed scenes from the Old and New Testaments and the lives of the saints, designed to teach people doctrines of the Christian faith. They also showed scenes from the lives of the artisans and merchants who paid for them.

Once at least part of a cathedral had been built, the building began to be used for religious services. Town residents gathered for masses, baptisms, funerals, and saint’s day services, and also used it for guild meetings and other secular purposes. Services became increasingly complex to fit with their new surroundings. Originally, services were chanted by the clergy in unison, in a form of liturgical music termed plainsong or Gregorian chant, but by the eleventh century additional voices singing in different pitches were added, creating what is called polyphony. Church leaders sometimes fumed that polyphony made the text impossible to understand but — along with incense, candles, stained-glass windows, statuary, tapestry wall hangings, and the building itself — music made services in a Gothic cathedral a rich experience.

The frenzy to create the most magnificent Gothic cathedrals eventually came to an end. Begun in 1247, the cathedral in Beauvais reached a height of 157 feet in the interior, exceeding all others. Unfortunately, the weight imposed on the vaults was too great, and the building collapsed in 1284. The collapse was viewed as an aberration, for countless other cathedrals were in various stages of completion at the same time, and none of them fell. In hindsight, however, it can be viewed as a harbinger. Very few cathedrals not yet completed at the time of its collapse were ever finished, and even fewer were started. In the fourteenth century the church itself splintered, and the cities that had so proudly built cathedrals were decimated by famine and disease.