Emperor Diocletian is believed to have ordered the construction of the palace with the intention of retreating into it after his previously arranged abdication. Historical facts mostly confirm such a theory.
It is certain that during his rule Diocletian campaigned against usurpers and rebels in Egypt. As much as 11 Egyptian sphinxes have been found within the walls of the Palace so far, whereas all columns in the palace are made out of the same granite used for the construction of many monumental Egyptian buildings. The construction of the Palace is symbolic of the new system of empire government instituted by Diocletian. As already mentioned, the rule of the empire was divided among four tetrarchs – four emperors, four divine creatures walking the Earth, which corresponded the four seasons. It is in this light that we can observe the central part of the Split Palace, along with the Peristyle and the four temples, which were not only built as mausoleums, but as a ceremonial area of the new cult of the divine emperor.
The ground plan of the Diocletian's Palace is an irregular rectangle, with longer sides of about 215 meters, and the narrower ones (the northern and the southern) of about 180 meters. The total area of the Palace measures approximately 30,000 square meters. The transversal street, linking the western and the eastern gate of the Palace, divides the complex into two halves. The southern side of the Palace was occupied by imperial apartments and ceremonial areas, whereas the northern part consisted of two large rectangular blocks which were reserved for the servants and soldiers quarters. The strong exterior defence walls were re-enforced by four massive square towers at the corners of the Palace, as well as two rectangular towers between the gates and each corner tower. Each of the landward gates was guarded by a pair of octagonal flanking towers, which made 16 towers altogether. The landward walls of the Palace were thrown open by large arching upper storey windows, whereas the southern facade facing the sea was also divided by cornices, corbels and half-pillars. A sentry walkway stretched along the walls of the Palace. As the medieval city was with time incorporated into the Palace, a large part of the original architecture was therefore preserved.
Approaching the Palace from land, we can see that the northern wall has been preserved in its full length. Although the octagonal and rectangular towers on the very walls have been destroyed, their earlier positions are still clearly visible. The large arching windows on the upper storey of the facade, although walled up, are also preserved and visible. The middle of the northern wall is adorned by the impressive Golden Gate – Porta Aurea. This was no doubt the main entrance into the Palace to which the road from Salona led. The main exterior ornament of the gate consists of two niches for statues on either side of the gate and three additional niches for statues right above it, along with extravagant arches which used to be supported by columns. The entire structure of the gate is further adorned by ornamented stone plastics of capitals and corbels. On the west side of the capital the Greek name ZOTIKOS is engraved, providing important information on the builder i.e. architect of the Palace. Four stone bases have been preserved above the wall, which most probably used to feature statues of Emperor Diocletian and the other three tetrarchs. The northern gate also contains an impressive defence courtyard with secondary gates, which was used to entrap the enemies who managed to enter the main gate. A part of the sentry corridor above the gate holds the medieval Church of St. Martin, which has preserved many of its Romantic elements until today: a stone altar partition with an inscription dedicated to St. Martin and the Blessed Virgin Mary, a door lintel with an inscription by priest Dominic, the barrel vault of the church and the three small windows set within the walled up arching openings of the original Palace facing the defence courtyard. The north-east tower was transformed into residential quarters in the 18th century. The original ancient wall of the tower was only preserved up to the first-floor level.
The eastern wall can also be observed in full length, although later additions to the Palace have disrupted the rhythm of the original facade openings. The rectangular and octagonal towers were pulled down in the 18th century, and the present appearance of the wall (especially of the part between the gate and the south-east corner tower) was largely influenced by the addition and later pulling down of the castle of duke Hrvoje Vukčić Hrvatinić (in the 15th century). The eastern gate (later called the Silver Gate) is similar in shape to the northern one, but much more modest in composition and ornamentation. Throughout the centuries they were partitioned or walled up on several occasions. In the 18th century a new, smaller gate was built in the eastern wall, a bit to the north from the original one. The Silver Gate was again opened and rebuilt in the 1940-es, whereas the inside defence courtyard was partly renovated in 1952.
The south-eastern tower originally consisted of the ground floor and 3 upper floors, and was by a floor higher than the northern towers. It has been preserved up to the second floor, which today has a terrace on top. In the medieval period the upper floors of the tower were part of the Archbishop's Palace. The second-floor windows have been walled-up, but are nevertheless clearly visible from outside the Palace.
Due to the fact that the city mostly spread westwards, the western wall has been least preserved – it was partly pulled down and partly built into new buildings which were erected over the centuries. The south-western tower was fully destroyed, whereas remnants of the western wall are most clearly to be seen at small square of „Mihovilova širina“.At the same square one can see the remains of the early medieval church of St. Michael „on the Shore“ (Sv. Mihovil) from the 7th and 8th century, which was the first church to be built outside the Palace walls. At the time of its construction, the church was actually situated at the very shore, since a cove stretched from the south-east corner tower over the whole area of the today's Braće Radić Square. In the Middle Ages the western gate, or the so called Iron Gate, represented the main line of communication between the old city nucleus within the Palace and the new city districts outside it. Although quite similar in appearance to the eastern one, the western gate has however been much better preserved, especially its defence courtyard as well as parts of the octagonal towers on their outer side. The sentry walkway above the inner gate houses the small church of Our Lady of the Belfry (originally St. Theodore). The original architectural elements which have been preserved within are the crossed-dome and the belfry dating from the 11th century, representing the earliest pre-Romanesque monument on our part of the Adriatic coast. Three small floors of the church are divided by characteristic openings. A decorative cornice is visible just below the ceiling, similar in shape to blind arcades which represent a typical ornament of the future Romanesque style.
The southern facade of the Palace differs significantly from the remaining three, since it was originally lapped by the sea. A relatively plain vaulted passage in the centre of the southern wall (colloquially known as the Brass Gate) used to serve as a direct water entrance for the incoming galleys. The ground floor originally contained a number of small openings which were later walled up but are nevertheless still visible from a long hallway inside the Palace. A long covered gallery over-looking the sea which extended along the entire southern facade consisted of a long row of arcades separated by half-pillars. The rhythmical row of arching windows was diversified by three-arched openings (loggias) in the centre and on both ends of the facade. The gallery provided an excellent view of the nearby islands, but also represented a direct communication line between various halls and imperial quarters of the Palace. Throughout the centuries the southern facade was divided by partitions and covered up by later additions to the building. With the expansion of the wharf a number of small houses were erected below the facade, which apart from historical also had an ambient importance. In the spirit of classicist purification at the beginning of the 20th century all of these later structures were demolished and replaced by buildings of traditional architecture typical of the German architect Keller. Although of no historical or artistic value whatsoever, these new buildings - with their row of ground floor shops and stores - nevertheless brought new life to Split's sea-front promenade (the so called Riva).
The Emperor's apartments occupied the entire southern quarter of the Palace at the second floor level. The ground floor (colloquially known as Diocletian's basements) merely represented a supporting substructure of the quarters on the upper floor. The original structure of the Emperor's apartment was mostly destroyed by later partitions, while the basement spaces have been well preserved.
The two basic axes of Diocletian's basements consist of the longitudinal one which ran through the central hall and the so called vestibule and the transversal axis representing the upper gallery along the entire southern facade, from which one reached all the remaining chambers of the residential block. A large central hall was flanked by a row of smaller quarters reserved for the imperial guards. The western part consisted of reception halls and the emperor's private quarters, whereas the eastern part included the entire dining complex as well as other quarters of an as yet unclear purpose. The still preserved vestibule used to be entered from the Peristyle. It actually represented an entrance hall and waiting room, rectangular in shape from outside and circular in its interior. The circular interior walls are broken up by semi circular niches and crowned by a dome on top. The cupola of the dome has been demolished. The walls were originally panelled with mosaics and ornamental marble plates. What has also been preserved of the first floor are parts of the „triclinium“ (the Emperor's dining room) and parts of walls of the western reception hall. The Triclinium derives its name from a Latin word with which the Romans denoted a couch they used for dining in a semi-recumbent position. The dining room of the Emperor's apartment took up a large portion of the eastern part of the Palace. It consisted of one large hall and three smaller halls with entrance areas. The large central hall of the dining complex was rectangular on the outside and octagonal on the inside, and additionally divided up by semicircular niches. A nun monastery of St. Clare was built within the Palace in the 14th century, but was moved outside its walls in 1883.
North of the triclinium an eastern complex of baths (thermae) was discovered. The discovered remains of the original baths include a semi-circular warm water pool, which used to be flanked by a bathing furnace on one side and a floor and wall heating system on the other. The substructure of the Palace (i.e. its basement) has been well preserved due to the fact that the basements, although partly inhabited by refugees from Salona themselves, were quite early filled up with debris and waste from the upper residential quarters. The largest central hall was excavated along with others in 1945, whereas systematic excavations began in 1955. The basement halls are today open for sightseeing and used as a venue for important cultural events.
The Peristyle is one of the architecturally most significant parts of the Palace. It encompasses quite a large area along the longitudinal axis of the Palace, framed from three sides by colonnades. The Peristyle court is three steps lower than the surrounding areas. It originally represented the main access area to the imperial apartments to its south, to the Emperor's mausoleum to its east, and to the three temples of the Palace to its west. The four high and slender columns with Corinthian capitals bearing a triangular gable above a semi-circular arch on the southern side of the Peristyle belong to the Protiron, which marks the monumental entrance into Diocletian's apartments. On special occasions the Emperor would appear on a balustraded imperial loggia which used to be situated between the central columns of the Protiron. The Peristyle was originally built as a ceremonial cult area, in which the Emperor would show himself to his subjects as a self-declared living God, and they would honour him by throwing themselves prostrate on the pavement. The space above the Protiron used to be adorned by a monumental sculpture, most probably a four-horsed carriage. The eastern and western side of the Peristyle, left and right of the Protiron, consist of colonnades, each with six slender Corinthian columns connected by seven arches with richly ornamented cornices. In the 16th and the 17th century two chapels were built within the Protiron (Our Lady of the Belt and Our Lady of Conception) and the central Baroque arch was added. The Emperor's mausoleum on the east side of the Peristyle was in the Middle Ages transformed into the present-day cathedral of St. Domnius, with a monumental bell-tower which was built in the period between the 13th and the 16th century. Et the very east end of the Peristyle the Renaissance church of St. Roch (Sv. Roko) is situated, re-constructed in 1516 from an earlier Romanesque house. The area west of the Peristyle is today closed up by a row of later medieval buildings. The ancient ceremonial court today serves as a venue for numerous musical events and theatre performances of the Split Summer Festival. As already mentioned, emperor Diocletian's mausoleum lies east of the Peristyle, in a rectangular courtyard closed in by a high wall. It represents a temple of the central (or circular) type with an exterior portico. The octagonal central building of the temple is encircled by 24 columns which support the coffered stone vault. The interior of the temple is circular in plan and divided by semicircular and rectangular niches. Two vertical rows of coloured stone columns bear richly ornamented cornices. The frieze just below the dome contains figurative medallions with portraits of emperor Diocletian and his wife Prisca, which are framed with a laurel wreath carried by winged boys. The same frieze also contains a hunting scene, which represents a typical motif of the burial cult. The centre of the mausoleum used to hold a sarcophagus with the late Emperor's body which was removed during the early Middle Ages. Situated below the mausoleum is a crypt, also circular in plan, which was transformed into the Church of St. Lucy in the Middle Ages. At the time when the Palace was being transformed into a city, the mausoleum first became the cathedral of St. Mary but it soon became known as St. Domnius cathedral, named by a martyr from Salona whose altar was erected within the cathedral in the early Middle Ages. The baroque choir area on the eastern side of the cathedral was added in the 17th century.
The south-west corner of the Peristyle accommodates a Romanesque/early Gothic palace, which underwent significant reconstructions during the Renaissance period, and was further altered by a Baroque balcony which protrudes from its Peristyle facade.
Along the north-west part of the Peristyle stands the Grisonogo-Cipci palace, which appears as though it was built into the western colonnade of the ancient court. During the renovation of the Luxor café (on the ground floor of the palace) a part of the flooring of the ancient Venus temple was discovered, along with parts of a Romanesque loggia with preserved column capitals and arches. In the 15th century the palace was divided and its southern part was given to the Cipci family, as the family’s coat of arms made in the manner of ornate Gothic, typical of the workshop of Juraj Dalmatinac, suggests. In the 16th century the Cipci family added another floor to the palace which was built in the Renaissance style, most probably by the workshop of Nikola Firentinac.
Southwest of the baptistery of St. John (originally the ancient temple of Jupiter) the complex of the western baths was discovered – i.e. the Roman thermae with remains similar to those found within the complex of the eastern baths, which indicates the same system of heating and water supply.
By the eastern gate of the Palace along the main transverse street (the so-called decumanus) stands a classicist palace of simple and unobtrusive lines and harmonious proportions which at the beginning of the 19th century used to accommodate the Classical Gymnasium. At the west side of the decumanus rises the Cindro palace, which is one of the most beautiful examples of Baroque architecture in Split.
Not much has been preserved of the large northwest complex of the Palace. The northern street which in the ancient period ran along the inner side of the northern walls was later transformed into a medieval street with a significant number of architectural works which have been preserved from the period. The ancient north-east building was preserved only in fragments of certain floor mosaics. What has remained intact of the ancient eastern street are the original massive pillars of the portico (i.e. gallery) which extended along the Palace walls. The area of the ancient northeast complex of the Palace is today intersected by a transversal medieval street (today known as Papalićeva Street) which boasts the impressive complex of the late-Gothic Papalić Palace, representing one of the most beautiful examples of Gothic-Renaissance architecture in Split. The courtyard of the palace holds a ground-floor loggia, and an exterior staircase leads to the upper floor which boasts a large main hall illuminated by an impressive and beautiful four-light window (i.e. „quadrifora“). The palace today accommodates the Museum of the City of Split which includes the Gallery Vidović, dedicated to the city's most significant painter of the 20th century.
During the 12th and the beginning of the 14th century the late-Romanesque bell-tower of the St.Domnius cathedral was erected. At the beginning of the 16th century another Romanesque floor was added to the bell-tower, whereas its construction was completed with a Gothic-Renaissance top. The impressive bell-tower has for centuries been a symbol of Split and the most prominent feature of the city’s visual identity. During the reconstruction of the bell-tower in the 19th century its Gothic-Renaissance top floor was replaced by a neo-Romanesque loggia, which caused it to lose some of its original vivacity. Two lion sculptures, similar in features to those in front of the Trogir cathedral, guard the very entrance of the bell-tower. On the first floor original scenes of the Annunciation and the Nativity have been preserved – based on the finery of their sculpting recognized as the work of Master Radovan, who was active in Trogir in the same period. Much rougher and more robust are the reliefs depicting St. Anastasius, St. Domnius and St. Peter, which bear the name of master Otto, clearly a sculptor of northern origin. The portrayal of a hunt in the arch of the vaulted passage of the bell-tower is also attributed to the same artist.
CHURCH OF ST. DOMNIUS
One of the best preserved examples of woodcarving are the wooden doors of the Split cathedral made in 1214 by master Andija Buvina. The doorframe was made out of walnut wood on a background of oak boards. Each of the two wings of the doors, which are 530 cm in height and 360 cm in width, contains 14 scenes from the life of Christ. The left wing depicts scenes from Christ's childhood, from angel Gabriel's Annunciation until Christ's Resurrection, whereas the right one contains scenes of Christ's suffering, death and ascension. The area between the 28 panels is ornamented by motifs of vine tendrils twining around people and birds picking grapes.
Left of the main entrance lies a richly ornamented stone pulpit, made in late-Romanesque style. Six slender columns with vividly decorated capitals represent the basis of the hexagonal pulpit, which is broken by a rich row of blind arches with double pillars of coloured marble, reliefs and symbols of the evangelists.
Wooden choir benches, elaborately furnished with typically Romanesque decorations, are placed in a later added Baroque choir from the 17th century. The choir seating represents a significant piece of wood-carving art dating from the 13th century, which shows influences of the Lombard Romanesque style but also certain elements of both Byzantine and Islamic decorations. Seven turned horizontal belts contain carvings with motifs of plant and animal life. The four ends of the backrest feature wooden reliefs of the patron saints of Split.
The south-east niche of the cathedral holds the altar of St. Domnius, consisting from an early-Christian sarcophagus and an early-Romanesque plate ornamented with an interlace pattern. A new altar in late-Gothic style was built above it in 1427 by the sculptor Bonino of Milan. The scene is dominated by a reclining figure of the saint covered with a stone baldachin, and the relief also contains figures of other saints. The stone vault (ciborium) above the altar is decorated with Gothic mural paintings, a work by the famous local painter Dujam Vušković. Twenty years later, in 1448, in the north-east niche of the cathedral master Juraj Matejev Dalmatinac (George the Dalmatian) built the altar of St. Anastasius, which represents a masterpiece of Gothic-Renaissance sculpture in Croatia. The central ornament of the altar is a realistic relief depicting the Flagellation of Christ.
The northern Baroque altar of St. Domnius was built in 1766./67 by the famous Venetian sculptor G.M.Morlaiter. The elaborately divided altar contains a sarcophagus supported by allegorical female characters of Faith and Constancy. The softly modelled relief on the front of the altar shows the scene of the martyr death of the first bishop of Salona.
The main Baroque altar of the cathedral occupies the arch leading through to the added choir. The vault above the altar is ornamented with Baroque paintings by the local master Matija Pončun.
The cathedral contains a number of valuable crucifixes dating from various periods.
The later added building of the sacristy on the southeast side of the cathedral accommodates the cathedral’s treasury which contains a number of valuable religious artefacts dating from the early Middle Ages until Baroque. These primarily include relics and liturgical artefacts made out of precious metals, liturgical books and old manuscripts as well as icons and valuable mass vestments. One of the most valuable books in the collection is the Split Evangelistarium from the 7th and 8th century, as well as the elaborately ornamented manuscript of Historia Salonitana, a chronicle of the Split church written in the 13th century by Thomas the Archdeacon, which today represents one of the most important sources for the study of the history of Split and the entire territory of Dalmatia.
On the west, within the axis of the mausoleum, rises the small temple of Jupiter. The temple was originally rectangular in plan, with elevated flooring and six columns forming a portico on the east side. Neither the columns nor the portico have been preserved. The right side of the temple entrance is decorated with a sculpture of an Egyptian sphinx.
In the Christian period the temple was transformed into the cathedral’s baptistery and its crypt into the miniature chapel of St. Thomas. The interior of the baptistery features the sarcophagus of Ivan Ravenjanin (i.e. John of Ravenna) , the founder of the new Salona archbishopric in Split, ornamented with relief motifs of lilies, as well as the sarcophagus of the archbishop Lovre (i.e. Lawrence) from the 11th century, who lead the church of Split during the period of Croatian rulers. The cross-shaped baptismal font was probably built in the 12th century and was obviously made of panels which used to be a part of an altar rail. The panels are richly ornamented with interlace patterns, and the most prominent among them features a relief of a pentagram and of birds eating grapes. Of equal artistic value is the stone panel from the 11th century on the frontal part of the baptismal font featuring a Croatian ruler on his throne. Based on the style of the relief, the panel is often associated with the Croatian ruler Dmitar Zvonimir. The baptistery also holds a bronze statue of St. John the Baptist from 1954, a late work of the famous sculptor Ivan Meštrović
Saint Domnius, the patron saint of Split, was born in Syria. According to the local tradition of the early medieval period, St. Domnius is believed to have been a disciple of St. Peter himself. According to historical facts, he was a Christian teacher and the first bishop of Salona who died as a martyr during Diocletian’s severe persecution of Christians at the end of the 3rd and beginning of the 4th century. He was buried in Solin. The former mausoleum of the Emperor Diocletian, which was meanwhile transformed into a Christian church, soon became known under his name.