Understanding the development of church architecture involves considering the requirements of religious ritual, the symbolism of architectural forms, and the demands of the society served by the church building.  The word church (from the Greek kyriakon doma, "the Lord's House") first described the building that housed the worshipers and later referred to the entire Christian community.

Early Christian Churches

The earliest Christians developed no ecclesiastical architecture.  They usually met in private homes, frequently in a dining room, because the earliest Christian service involved a ritual meal.  The dining room was often the only large room in the house, frequently occupying the entire top floor;  this is the upper room often mentioned in Acts.  The upper room was at first furnished with a table and three surrounding couches; but as the Christian community expanded and the liturgy developed, the assembly rooms became larger.  By the 3d century, they were furnished with a special table, or mensa, for the Eucharist.  The officiating bishop sat near this \Taltar\t in an armchair, or cathedra;  this chair eventually gave its name to the cathedral, which, in contrast to a parish church, is one over which a bishop presides.

From AD 313, when Emperor Constantine I granted Christianity official status throughout the Roman Empire, Christian liturgy became increasingly imperial in tone.  A new and more dignified architectural setting was required for the liturgy, and Constantine's architects turned for inspiration to the Roman \Tbasilica\t, a type of large public meeting hall used primarily as a law court.  The Early Christian basilica (see \TEarly Christian art and architecture\t) was a longitudinal structure with a central \Tnave\t flanked by two or more side aisles of lower height;  the nave was lighted by the \Tclerestory\t, a row of windows above the aisle \Tarcade\t, and terminated in a semicircular \Tapse\t.  The clergy sat in the apse--as the magistrates had in the law courts--separated from the laity by a railing or screen.  In Byzantine churches the clergy were isolated even more from the laity by an \Ticonostasis\t, a screen wall covered with holy pictures, or \Licon\ls.  Behind the closed doors of the iconostasis the priests performed the rite of the Eucharist.

The Early Christian basilicas, such as Old \TSaint Peter\t's \Tbasilica\t in Rome (dedicated c.330;  destroyed in the 16th century) were fronted by an \Tatrium\t, or courtyard and a NARTHEX (porch) leading to the nave, which was crossed by a \Ttransept\t (transverse aisle) that separated the nave from the apse.  The cruciform ground plan had obvious symbolic appeal, and the longitudinal focus placed the worshiper entering the church in a direct axial relationship to the sanctuary in the apse.  This focus was reinforced by the rows of aisle columns, which created a powerful perspective focusing on the altar.

Early Christian architects also developed the centralized plan, based on the circle, the square, the polygon, and the Greek cross (arms of equal length).  In a centralized plan the center of the structure becomes the liturgical focus of the church. For example, in the round church of Santa Costanza in Rome (mid-4th century), a shadowy barrel-vaulted ambulatory (circular aisle) encircles the central domed space of the church.  The \Tdome\t was universally understood from Roman imperial times to symbolize the dome of heaven, and Santa Costanza's dome, echoing the domed circular tombs of Roman emperors, suggests that this church, which housed imperial family tombs, may have been built as a memorial to an emperor.

Byzantine Churches

The centralized domed plan, embodying the concept of Christ as the heavenly ruler, and the basilican plan, stressing the public and processional character of the mass, were merged in the great church of \THagia Sophia\t (532-537), built by the Emperor Justinian I in Constantinople (now Istanbul), capital of the Byzantine Empire (see \TByzantine art and architecture\t). The majestic interior is covered at the center by a wide, shallow dome that seems to float on a ring of light formed by 40 windows around its drum.  The dome is supported by pendentives (spherical triangles) on four immense piers at the corners of the square core of the church.  The square central space is extended east and west by a series of semicircular half-domed apses diminishing from full nave width to one-third, to form an enormous longitudinal basilica.  This entire lofty space is surrounded by two-story subsidiary areas with balconies on the second level, from which the women and the commoners watched the mass.  They had only a partial view of the ceremony, which took place in the presence of the emperor, his court, and the clergy behind the iconostasis that screened the sanctuary in the apses to the east.

Early Medieval Churches

In his desire to revive the glories of the imperial past, Charlemagne abandoned the simple Merovingian church prototypes (see \TMerovingian art and architecture\t) and based the plan of his Palace Chapel (c.800) at Aachen, Germany, on a centralized Byzantine model, Justinian's octagonal Church of \TSan Vitale\t (526-547) in Ravenna, Italy.  The basilican plan, however, which was deliberately revived during the Carolingian renaissance (see \TCarolingian art and architecture\t), dominated Western ecclesiastical architecture of the Middle Ages.  The abbey church of Saint Riquier (c.800;  destroyed) at Centula in northeast France was a three-aisled basilica with transept arms;  it exhibits features, unknown in the earlier basilicas, that had considerable impact on church architecture in the later Middle Ages:  the entrance structure known as the westwork and multiple towers integrated into the structure on the exterior.  The spiky silhouette of this building influenced the later Ottonian churches (see \TOttonian art and architecture\t) of Germany, such as Saint Michael's in Hildesheim (1001-31), which retains the towers and westworks of Saint Riquier.

Multiple towers appear on some German early Romanesque churches, such as the Cathedral of Speyer (begun 1030) in the Rhineland, and they appear in the next century, transformed into the heaven-piercing spires of the Gothic cathedrals of France and England.

Romanesque Cathedrals and Churches

The Romanesque (see \TRomanesque art and architecture\t), an age devoted to travel in many forms, from the Crusades to pilgrimages, saw the development of such pilgrim churches as Saint Sernin (begun c.1080) in Toulouse, on one of the routes through southern France to the shrine of Santiago de Compostela in northwestern Spain.  Saint Sernin's round arches and heavy masonry walls recall Roman architecture, which gave the Romanesque style its name.  The vaulted masonry ceiling of the church reflected the desire for a more fire-resistant roof than the wooden ceilings of earlier medieval churches.  The church forms a large Latin cross;  the four side aisles and extended nave were created to accommodate the hordes of pilgrims. Circulation through the church was facilitated by extending the side aisles around the apse to form an ambulatory.  The small radial chapels opening off the ambulatory and transept arms provided a setting for the subsidiary altars needed to serve the numerous worshipers;  the radial chapels were also used to display the holy relics brought back to western Europe in quantity by the Crusaders.

The Romanesque style varied from country to country;  the Cathedral of Pisa, famous for its leaning \Tcampanile\t (bell tower;  begun 1063), is the work of Italian Romanesque architects.  The most progressive Romanesque architecture, however, was practiced by the Normans (see \TNorman architecture\t).  The west facade of the Norman church of Saint Etienne at Caen, begun under the patronage of William the Conqueror in 1067, looks back to the Carolingian and Ottonian westworks.  The facade, surmounted by twin towers, is divided by massive vertical buttresses into three vertical bays reflecting the interior arrangement of nave and side aisles. \TDurham Cathedral\t in England (begun 1093) exhibits two forward-looking aspects of Norman architecture:  the use of pointed arches and ribbed groin vaults.  These allow the use of windows that admit light directly into the nave, thus overcoming a problem found, for example, at Saint Sernin, Toulouse, where the dark nave has no windows and gets only indirect light from small windows along the side aisles.

Gothic Cathedrals and Churches

For the builders of Gothic cathedrals (see \TGothic art and architecture\t), bringing light into the nave by using the ribbed groin vault was not only a practical matter, but also involved theological considerations, for the sunlight entering these buildings through their enormous stained-glass windows, a light from heaven, was equated with the divine radiance.  The pointed arch, a characteristic device of Gothic architecture that permits the construction of taller cathedrals, draws the eye upward, toward God.  Another technical device that allowed Gothic builders to produce their soaring, light-filled structures is the flying \Tbuttress\t, which rises up on the exterior of the building and supports its thin upper walls. Flying buttresses allow the removal of almost all supporting elements of the building to the exterior.  This results in the luminosity and seeming weightlessness of such French High Gothic interiors as that of \TAmiens Cathedral\t (begun 1220);  the intricate "skeleton" of the building is visible only on the exterior.

The facades and doorways of the Gothic cathedrals, which faced the newly prosperous cities in which they were built, were covered with elaborate scriptural programs of sculptural decoration that were "read" by the townspeople as they entered the church.

Gothic architecture has been equated with the scholastic philosophy of its day;  in both, the insistence upon an order and a unity composed of separate but related parts is meant to reflect the order and unity of the elements of God's universe.

Renaissance Cathedrals and Churches

For much of the 15th century, Italian Renaissance (see \TRenaissance art and architecture\t) churches were for the most part longitudinal.  They differ from their Gothic predecessors in style and in the orientation of the structuring members of the church to a humanistic ideal:  the ideal human was Christ and the divine order of the universe must be reflected in the mathematical proportioning of all the parts of the church to one another.  Filippo \TBrunelleschi\t's Church of San Lorenzo (begun in 1421) in Florence, for example, is a three-aisled, Latin cross plan with transept;  the unifying elements in it are the square module on which all of the church was designed and the consistent application of the classical orders.

Learning from Brunelleschi, the great 15th-century architect and theoretician Leon Battista \TAlberti\t voiced the Renaissance view in calling a church (or "temple," in Renaissance parlance) the greatest and noblest ornament of a city.  Thus he demanded a prominent site for a church--its location in a square and its elevation above the surrounding buildings--so that all of its parts could be admired.  Moreover, geometrical proportions must govern the structure in every detail.

The ideal Renaissance church type was based on the centralized plan, exemplified by Brunelleschi's remarkable design for Santa Maria degli Angeli (1434-37) in Florence, an entirely centralized church formed by a ring of eight piers.  Architects and theoreticians admired the centralized plan for its geometrical purity and clarity, directly relatable to heavenly order.  The first to be built almost to completion, however, Guiliano da \TSangallo\t's Madonna delle Carceri (begun 1484) at Prato, shows the inherent difficulties imposed by such a plan (here the Greek cross):  geometrical focus is at the center of the plan, whereas the religious or liturgical focus, the altar, is set for practical purposes in the arm of the church opposite the main entrance.  Thus there is a conflict between the geometry of the plan and the implied longitudinal axis.

Nevertheless, centralized plans were popular during the brief period of the High Renaissance (c.1500-20), and in 1506 Donato \TBramante\t proposed a central plan for the new Saint Peter's Basilica, when Pope Julius II (1503-13) decided to replace the old Constantinian basilica.  The historical details are complex, but after the deaths of Julius II, Bramante, and, in 1514, \TMichelangelo\t, who was Bramante's successor as architect, religious conservatism had apparently run out and a longitudinal nave for the new basilica was tacked on the partially completed centralized domed church.

Baroque and Rococo Churches

After the sack of Rome in 1527, longitudinal churches returned to favor.  Antonio \TSangallo\t the Younger's Church of Santo Spirito (1538-44) in Sassia illustrates the new thought:  a single-aisle church flanked by shallow chapels leads to a large high-altar chapel in the wide apse.  In the 1530s the Jesuits had already instituted year-round preaching instead of preaching only at Lent, and in Santo Spirito the nave, with a flat wooden ceiling, serves the double purpose of providing an audience hall for preaching and congregational space for mass. Giacomo \TVignola\t's Church of Il Gesu, begun in Rome for the Jesuits in 1568, shows the full development of a new style, the baroque (see \Tbaroque art and architecture\t).  It is a large, single-aisled church, with truncated transept arms and a large dome over the crossing, all leading to the altar set in a deep, wide apse.

Subsequent church building for the Roman Catholic rite followed previous examples, but the number of regions and changes of style produced enormous variety within the rules laid down in the enactment of the Council of Trent in 1564.  In the north, especially in Austria and Germany, the baroque and \Trococo style\t found exuberant expression, as in Johann Balthasar \TNeumann\t's Vierzehnheiligen (Fourteen Saints) Church (1743-72) near Bamberg.  In the Roman Catholic countries of northern Europe, church plans developed much as they did in Italy, but the Gothic style endured more steadily in the north until gradually replaced by Italianate forms, and steeples continued to be dominant architectural elements.

In the Protestant north, particularly in Holland, congregations took over the Gothic churches that survived the religious wars, stripping them of most of their decoration.  Stylistically, the Dutch remained attached to the familiar Gothic idiom and to the bell towers that denote the presence of churches in a city. The most pronounced changes were in the mode of worship:  Roman Catholic ritual was replaced by a new emphasis on preaching, which required good lighting and pulpits.  In the Zuidekerk (begun 1606) in Amsterdam, Hendrik de \TKeyser\t designed a simple pseudobasilica, without a choir but with large windows and a large wooden pulpit around a central column-pier.

Neoclassical Cathedrals and Churches

After the Great Fire of 1666 in London, Sir Christopher \Twren\t, one of the greatest of English architects, gave the city a new skyline with the dozens of steepled churches he and his brilliant pupil Nicholas \THawksmoor\t created.  Dominating them all with its massive dome on a high, pillared drum is \TSaint Paul\t's \Tcathedral\t (1675-1711), a vast Latin cross basilica rivaling Saint Peter's in size and splendor.  Wren's parish churches are exemplified by the elegant Church of Saint Clement Danes (begun 1680), a galleried church with shallow vaults over the nave and aisles.  In the United States \Tneoclassicism\t found late but impressive expression in Benjamin \TLatrobe\t's Roman Catholic Cathedral of Baltimore (1804-18), a shallow-domed Latin cross plan with segmental barrel vaulting of the nave and side aisles.

Churches in the 19th and 20th Centuries

Church architecture in the 19th and early 20th centuries was dominated by a succession of revival styles, the major ones being \TGreek Revival\t, \TGothic Revival\t, and Romanesque Revival. The resultant buildings range from tawdry pastiches to splendid eclectic creations, many of which in the latter category are now considered national treasures.  Such is the case with H. H.  \TRichardson\t's Byzantine-Romanesque Trinity Church (1872-77) on Boston's Copley Square, and with James \TRenwick\t's Grace Church (completed 1846), a sensitive interpretation of English Gothic in New York City.

Contemporary church architecture is not noted for its distinction, with very few exceptions.  \TLe Corbusier\t's stunningly original pilgrim church of Notre Dame du Haut (1950-55) in Ronchamp, France, Eliel Saarinen's serene First Christian Church (1942) in Columbus, Indiana, and the controversial new \TCoventry Cathedral\t (1954-62) in England stand out in an uncrowded field.  The world's largest cathedral, in the Ivory Coast in Africa, was completed in 1989.

The recent liturgical reforms in the Roman Catholic church and in several of the Protestant faiths, allowing for a freestanding altar with the priest celebrating mass facing the congregation, has already engendered promising new designs that may yield new solutions to the problems of ecclesiastical architecture.  EDWARD T.  \TMcClellan\t

Bibliography:  Anderson, William, and Hicks, Clive, Cathedrals in Architecture (1962);  Chamberlin, Russell, The English Cathedral (1987);  Cook, G.  H., The English Cathedral Through the Centuries (1965);  Cormack, Patrick, English Cathedrals (1984);  Fitchen, John, The Construction of Gothic Cathedrals (1977);  Frankl, Paul, Gothic Architecture (1962); Grunenfelder, Josef, Cathedrals of Europe (1976);  Krautheimer, Richard, Early Christian and Byzantine Architecture (1965; repr.  1975);  Rodin, Auguste, Cathedrals of France (1960; repr.  1981);  Ruskin, John, et al., An Illustrated Architectural History of the Greatest Cathedrals of the World, 2 vols.  (1986);  Short, Ernest H., History of Religious Architecture, 3d ed.  (1951);  Swaan, Wim, The Gothic Cathedral (1970);  Von Simson, Otto, The Gothic Cathedral (1988); Watson, Percy, Building the Medieval Cathedrals (1976).

See also: \Tarch and vault\t; \Tmonastic art and architecture\t.