Split is the chief mainland portin central Dalmatia, and Hvar islanders gravitate to it for shopping, cultural events, hospital visits, complicated bureaucratic affairs and lawsuits. Split is also the gateway to other parts of Croatia and the world. Locals by and large take for granted the historical treasures of the city environment, which for centuries were ignored, destroyed or allowed to decay. In modern times, however, major archaeological investigations have been unfolding quietly alongside renovations, under the aegis of the Ministry of Culture Conservation Office in Split.
A LUXURY RETIREMENT HOME?
Diocletian’s Palace forms the heart of modern-day Split, the main city in Croatia’s coastal region of Dalmatia. Considered a particularly fine example of the preservation of buildings through succeeding historical periods, the historical complex based on Diocletian’s Palace was inscribed in the UNESCO World Heritage List in 1979.
For centuries, it was thought that the Emperor Diocletian (c. 245 - c. 316 CE) planned and built his splendid palace in Aspalathos (also known as Spalatum) as a residence for his retirement, in which he could enjoy a peaceful life pottering about in his kitchen garden growing prized cabbages. This view coloured the interpretation of the surviving elements of the Palace buildings.
The assumption seemed reasonable for many reasons. The Palace was more or less completed in 305 CE, the same year in which Diocletian abdicated. There are no known written records about the palace’s concept, design and construction. Much of it was subsumed into a hotch-potch of dwellings as people fleeing marauders during succeeding centuries moved into the safety of its walls. The Palace’s pagan artefacts and symbols were mostly dispersed or destroyed after the temples were converted for Christian use. Significant parts remained of the core of Palace buildings, walls and towers, but there was virtually no trace of Diocletian having built anything outside its enclosures.
In the absence of written sources, knowledge about the Palace depended on an analysis of what remained to be seen above ground, and what could be uncovered through excavation. The narrow streets make renovation and conservation works extremely complicated. A further difficulty is striking a balance between preserving relics from the past and allowing property owners to use or develop their land or buildings which turn out to be historically significant. As Split is a thriving city, many finds have come about by chance during the construction of modern buildings.
IMPERIAL VILLA?
Historians and archaeologists have argued for many years about the correct designation for the Palace, because there was so little evidence about the use of its various parts, especially in the northern section, and it appeared to lack some of the attributes of ‘genuine’ imperial palaces such as those in Antioch and Constantinople. Should it be called a palace (palatium), military camp (castrum), a country estate (villa) or some other name?
Many early writers referred to it as a villa. It was not unknown for Roman Emperors to build themselves extended private estates which were termed ‘villas’. The Emperor Hadrian (76 - 138 CE), who reigned from 117 to 138 CE, built himself an extravagant complex with over 30 buildings at Tibur, modern-day Tivoli, 29 km from Rome, then capital of the Roman Empire. Apart from the imperial palace for the Emperor and residential buildings for his courtiers, Hadrian’s Villa contained several temples, state rooms, baths (thermae), libraries, a theatre and a mausoleum, among many other facilities.
‘Diocletian’s Palace’ has for centuries been the accepted term for the whole complex within the fortifying walls. It consisted of three main sections: the northern part, whose functions have not been established; the southern part, which we refer to as the Imperial Quarters; and the Temenos or temple enclosure between the two.
DIOCLETIAN: FROM HUMBLE ORIGINS TO DIVINE STATUS
Born in Dalmatia and originally called Diocles, Diocletian was a man of humble origins. He rose to success as a military man, and became Emperor by army acclaim in 284 CE, following the deaths of the Emperor Carus and his son Numerian.
He adopted the names Gaius Aurelius Valerius Diocletianus when he became Emperor. Besides the title Augustus, he was Sol invictus (the Unvanquished Sun) and Diocletianus Jovius (Diocletian Son of Jove / Jupiter, who was, of course, King of the Gods in Roman times).
In November 285 CE, Diocletian divided the Empire into East and West sections, and appointed his military comrade Aurelius Maximianus as Caesar in the Western Empire. In 293 CE, Diocletian established the Tetrarchy. Now there were two Augusti, and they kept power in the family by appointing their sons-in-law as their deputy Caesars. Each Tetrarch had his own administration and capital city.
Of the eight Roman Emperors before Diocletian, all are thought to have been assassinated, often by their own guards, four of them dying within a year of assuming power. Diocletian took great trouble to protect himself, and did not allow any armed personnel close to him.
Diocletian was clearly a man of determination, discipline and order, a ruthless military leader who used his powers to the full. He evidently inspired loyalty, and was prepared to trust those who had proved their worth. He was apparently devoted to his wife Prisca and daughter Valeria, unusually so for a Roman Emperor. He was practical, a man of action and politics as well as show. He travelled almost incessantly around the Empire throughout his reign. Apart from taking part in extensive military campaigns, he introduced monetary reforms and a more unified taxation system, to finance both his army and his ambitious building programmes. He increased the number of provinces in the empire, and created a new tier of local government with twelve so-called dioceses, each comprising several provinces. In the interests of political stability, he guaranteed bread for all Roman citizens, as well as spectacular shows and games.
In Diocletian’s view, traditional Roman religious practices were vital for maintaining unity and order in the Empire. He and his co-Emperors restored and built numerous temples throughout the Empire, reviving and following the ancient Roman traditions. He was savage against perceived threats: once persuaded that newer mystical religions could undermine political stability, he ordered the persecution of everyone who refused to sacrifice to the Roman gods, resulting in the relentless persecution of Manichaeans (from about 302 CE) and Christians (from 303 CE).
Diocletian asserted his authority on every level. His seniority over his co-emperor was defined through Maximian’s designation as Herculius, (son of Hercules), Hercules being the son of Jupiter in the hierarchy of the gods. Diocletian introduced a strict protocol of etiquette to his court, where visitors had to prostrate themselves before the Emperor and kiss his purple robe. The distance he created between himself and his subjects was both for his safety and to reinforce his supreme and divine status.
DID DIOCLETIAN REALLY PLAN FOR A SIMPLE RETIREMENT?
Although the Tetrarchy was designed to ensure a peaceful succession after the reign of the two Augusti, there is no evidence that Diocletian foresaw, let alone planned the eventuality of retirement before being compelled to by illness in 304. Diocletian was the first Roman Emperor ever to abdicate, and no other Emperor had outlived his reign, so there was no precedent for retirement.
The building of the Palace in Aspalathos started in about 295 CE, when Diocletian was very much in power. Aspalathos was some six kilometres from Salona, capital of the Province of Dalmatia, and was also convenient for the transport of stone from the stoneworks near the port of Splitska on Brač Island.
This Palace was by no means the only major building project in the Empire during the years before Diocletian’s abdication. All the Tetrarchs established centres with palaces, and Diocletian himself conducted an extensive building programme in different parts of the empire. Contemporary writer Lactantius described him as having a lust for building (‘cupiditas aedificandi’).
It was only when he fell ill during a tour of the Danubian territories in the summer of 304 CE that Diocletian’s ability to rule was undermined. He abdicated on May 1st 305 CE, simultaneously with a reluctant Maximian. By this time the Palace at Aspalathos was evidently ready for habitation, and Diocletian retired to his native land. Even after his abdication, he continued to advise his successors. He was invited to return to power in 308 CE, but refused on the grounds that growing vegetables successfully was more satisfying than being Emperor, as reported by Aurelius Victor in 361 CE: “Utinam Salonae possetis visere olera nostris manibus instituta, profecto numquam istud temptandum iudicaretis”.
Diocletian had reigned as an autocrat, despite spreading some of the administrative burden among his trusted co-emperors. Although he reverted to his original name of Diocles, he took on the title of Senior Augustus on abdicating, and retained the titles of Jovius and Sol invictus. Thus he renounced the everyday responsibilities of earthly power, but kept the aspects of divinity which he had assumed on becoming Emperor.
THE AQUEDUCT, A KEY TO THE PALACE - BUT WHICH DOOR DOES IT OPEN?
Salona, as capital of the Roman Province of Dalmatia, was supplied with water via an aqueduct with its source in the spring of the Jadro River. Built during the reign of the Emperor Augustus (27 BCE - 14 CE), the aqueduct was 3.850 km long and channelled up to 12,000 m3 of water per day. Diocletian enlarged and extended the aqueduct to supply up to 129,600 m3 per day. Thus Aspalathos had a bigger water supply than Salona, which at the time had a population of about 60,000.
TEXTILE WORKS IN ASPALATHOS
One of the few certainties about Aspalathos in Diocletian’s day is that it contained textile works, as the office of textile works manager, ‘Procurator gynaecii Iovensis Dalmatiae - Aspalato’, is listed in ‘Notitia Dignitatum’, a comprehensive document listing Roman officials and their administrative offices up to the late 4th and 5th centuries.
Textile production was extremely profitable, and Diocletian made the whole purple dyeing industry a state monopoly. There were numerous textile production and cloth dyeing facilities around the Empire, including at Salona.
A lot of water was needed in textile production. Aspalathos was close to a river, which, together with the extended aqueduct, meant that water was plentiful. Sulphur was used in the bleaching process, and Aspalathos had sulphur springs, near the present-day fish market. These might have been among the reasons for Diocletian choosing Aspalathos for his Palace.
DIGGING AND THINKING OUTSIDE THE BOX
Excavations at two sites outside the Palace walls have shown that Diocletian’s building project at Aspalathos was more wide-ranging than previously thought.
The Amphitheatre
In 2013 digging for a new shopping mall to the north of the Palace revealed the outline of part of a Roman amphitheatre with a span of 50 metres dating to the early 4th century CE. The aqueduct was found to have skirted round the eastern stands, proving that the two structures were planned and built in tandem. The remnants of stands were found in previous excavations, but were thought to belong to a theatre or odeon. The latest investigations have shown beyond doubt that they were part of an amphitheatre.
Outisde the amphitheatre, excavations uncovered Christian sarcophagi. It is thought that the two Christian churches found nearby were so-called martyrs' churches, established sometime after Diocletian's reign.
The Riva
Along the western half of the waterfront (riva) south of the Palace, excavations in 2006 and 2007 showed that the south wall was not built directly on the waterfront, as previously thought. The popular image by Ernest Hébrard portraying the Palace as a Villa Marittima is incorrect. In fact, there was a wall from before Diocletian’s time just over 12 metres away from the Palace’s south facade, and a thick layer of concrete dating to Diocletian’s time which extended along the waterfront to a length of about 180 metres, which is roughly a stadion (unit of measurement). The sea level in Diocletian’s time was nearly two metres lower than now, so the concrete structure would have been above the water.
How far the concrete structure extended southwards towards the sea is not known. It may have been a stadium: the lower part of the Palace’s south wall contained no openings apart from the modest doorway, so it is possible that spectator stands were banked against it. The majestic Serlian windows in the upper part of the south wall, which were only accessible from the Imperial Quarters, suggest that they were viewing points for important events in the space below on the seafront. (The central window, which was reached through a portico in line with the Porta Aurea, is now walled up.)
Whatever was in front of the Palace, the findings tend to confirm that the length of the south wall, in differing from the north wall, was no error. Following the excavations the seafront was paved over, covering all trace of the Antique structures. Plans are in hand to excavate the eastern half of the waterfront.
DISCOVERING DIOCLETIAN’S PALACE
It took several centuries for historians and travellers to take an interest in Diocletian’s Palace, by which time much of its detail had been altered beyond recognition. Attention was concentrated on the compact area inside the massive walls which defined the Palace.
The walls formed a trapezium, not a rectangle. Nor was the alignment of the Palace as one would expect: it did not follow the centuriation of the ager salonitanus. The site required a lot of preparation, especially in view of the sharp slope downwards on its south side. It was not chosen arbitrarily.
WALLS, STREETS AND TETRAPYLA
The north wall measured 174.74 metres, the south wall 181.65 metres, the west wall was over 200 metres, with the east wall slightly longer. The walls on the three landward sides had sentry pathways, while the south wall overlooking the sea did not. The internal space was divided by the main streets, the cardo running north-south from the main gate, known as the Porta Aurea (Golden Gate), and the east-west decumanus linking the Porta Argentea (Silver Gate) with the Porta Ferrea (Iron Gate). On the south side towards the sea, at the level of the Basement or Cellars (Podrumi), there was, and still is, an entrance which was modest by comparison with the others. This is commonly referred to as the Porta Aenea (Bronze Gate), which is probably incorrect. It was clearly a kind of service entrance.
The Porta Aurea, which was the main entrance leading directly from the Salona - Aspalathos road into the Palace, was ornate and grand, with strong double doors. It had five niches above the gate on its outer side, which probably contained statues of the Tetrarchs, perhaps with a representation of Jupiter or Apollo in the centre. The designation of metals for each entrance, if it is correct, usually referred to historical eras. The golden age was a time of peace and plenty characterized by olives and beehives.
Both main streets were some 12 metres wide, and originally had covered walkways to either side. Buildings now encroach on them in great part. An imposing colonnade flanked the southern part of the cardo, as it does to this day. This was known as the Peristylium in Robert Adam’s time in the 18th century, today as the Peristyle. The Palace Peristyle was more of a forum or gathering-place than a street. It is generally accepted that the cardo as a thoroughfare ended where it met the decumanus.
THE PALACE ENCLOSURE
Under the southern section of the Palace the ground sloped away. An extensive series of archways and galleries known as the Basement supported the structures above. The Basement was rectangular, by contrast with the trapezium above it. It is thought that one possible explanation for the asymmetry was the need to preserve previous sacral sites, of which some remnants have been discovered in the Imperial Residence in the eastern part of the Imperial Quarters.
The Basement layout has given some clues as to the layout of rooms above. Diocletian’s private residence had winter and summer rooms built on either side of a dining area (Triclinium). Imperial baths (thermae) have been discovered on the western side. There was a large hall in the centre of the southern area, which has been termed an aula or salutatorium. Between the Aula and the thermae was a room which may have been a Consilium Sacrum.
THE PROTIRON
Dominating the centre of the end of the cardo was the Protiron, a rectangular lobby supported on four massive red granite columns. The Emperor’s processional path (adventus) led from the Porta Aurea along the cardo and Peristyle to culminate at the Protiron. The Protiron was a grand setting where Diocletian could stand to receive homage from the people gathered in the Peristyle below. It was comprehensively restored between 2004 and 2012.
THE TETRAKIONION OR TETRAPYLON
At the crossroads of the two main streets, excavations under the original Roman paving revealed a base construction measuring 12.36m by 12.36m, with a cruciform ground plan and four foundations in the corners. During excavations in 1959 - 1960, it was thought to be the placement for a groma for accurate alignment. The discovery of the true extent of the foundations, which filled the whole space of the cardo-decumanus intersection, suggested that they could be the base for a Tetrakionion or Tetrapylon, whose purpose was to create an imposing entrance to a sacral area, symbolically marking a transition from the earthly domain to the territory of the gods. In the photograph below, Radoslav Bužančić indicates where one part of the support structure was sited, under the present-day stone pavement.
The base contained an equidistant cross formed by pebbles set in a hard mortar at its centre. Symbolically, the isosceles cross represented the unification of the material and ethereal worlds. The cross was paved over in Diocletian’s time, as it is today, but it would have been a significant symbol on the threshold of the entrance to the sacred area of the Palace.
THE TEMENOS
On either side of the Peristyle were temples in the sacral area (Temenos) enclosed by walls. The Temenos was separated from the Imperial Quarters by a trench, a common safety precaution in Roman times, especially against fire. The entrance to the sacred area on either side of the Peristyle was marked by four red granite columns, matching those of the Protiron.
Only two temples were still visible by the 16th century. Evidently there had been more: Thomas the Archdeacon in the 13th century described three temples, dedicated to Jupiter, Aesculapius and Mars, while in the 16th century Antonio Proculiano stated that there were four, dedicated to Janus, Cybele, Venus and Jupiter.
Inevitably, there is confusion about which god or gods each temple might have been dedicated to. In particular the rectangular temple in the west of the Temenos (now the Baptistery) is often referred to as Jupiter’s, although it is more generally accepted that the Mausoleum to the east (now the Cathedral of St. Doimus) was the Temple of Jupiter.
The Small Temple
The shapes of the temples were significant. To the Romans, the square shape symbolized the earth realm. The four sides represented the four seasons and directions, also the sun’s phases of two solstices and two equinoxes.
It is feasible that the rectangular western temple was dedicated to Janus, the god with two faces who represented beginnings and transition, and was the guardian of gates and doors. In the absence of certain proof, the term ‘Small Temple’ is often used, even though this was possibly not the smallest temple of the four. It has retained its original intricate carvings around the doorway and the top of the walls externally, and internally the coffered barrel-vaulted ceiling which enclosed the cella.
The Temples of Cybele and Venus
The remains of a small round temple to the west of the Peristyle, opposite the Mausoleum, were first uncovered by chance in 1851 by Vicko Andrić, Split’s first Conservator, during digging for a drainage channel. The discovery was evidently considered unimportant, as it was not mentioned again in academic studies for over one hundred years, when it resurfaced during excavations led by Jerko Marasović in 1957. Parts of a coffered ceiling were found, and these are now on display in front of a restored part of the temple wall on the refurbished ground floor of the Skočibučić-Lukaris Palace, which opened as an exhibition gallery in 2014. The crypt of the temple, which was filled with water sometime during the past centuries, is still under exploration.
This round temple is known as the Temple of Cybele, although there is no definitive proof that this attribution is correct. Cybele was originally a mother goddess in Anatolia. The Romans revered her as the Magna Mater (Great Mother), and she was considered a goddess of protection. In ancient times the circle represented perfection and the heavenly sphere, as well as the cyclic movement of perpetual renewal.
The 1957 excavations in the western Temenos also revealed the remnants of a second small round temple, north of the Temple of Cybele. This was attributed to Venus, who was also considered a mother to the Roman people. She represented love, sensuality and sexuality. Part of the floor of this temple is preserved in the present-day cafe Luxor on the west side of the Peristyle.
The Mausoleum, Temple of Jupiter
The best-preserved of the four temples is the Mausoleum, which was certainly planned as the resting place for Diocletian and Prisca’s remains. At the entrance to the Mausoleum there was at least one sphinx, which was described as an image of Cybele, bearing on its head a pillar topped by a statue of Jupiter. It is not known which direction the sphinx(es) faced.
Most of the pagan artefacts, including Diocletian’s sarcophagus, were removed by the time the temple was converted into the Christian Cathedral in the 7th century CE. The building still has its original pillars and carved capitals, and most of the original frieze around the upper segment of the walls. The cupola of the Mausoleum remains, but without its mosaics. Parts of a black and white checkered floor were uncovered in front of the side altar to St. Anastasius. At first this was thought to be the original Roman floor, but further digging revealed that it dated to the founding of the Cathedral in the 7th century CE.
The original Roman floor consisted of large stone slabs, which were probably re-used in later construction works.
More of the 7th century stone floor has been uncovered, bit by bit.
Where there is now a window disrupting the centre of the frieze on the east wall opposite the door, there would have been an image, possibly that of Jupiter or Sol Invictus. To the right of this is a relief of Diocletian, to the left one of his wife Prisca. In the central medallion of the frieze on the west wall is a head, thought to be of Hermes Psychopompus or Mercury, the god of transitions, among other things, who helped humans to cross the boundary into the other world when they died. As Son of Jupiter, Diocletian expected to be raised up into apotheosis after his death, and the decoration of the Mausoleum was designed accordingly.
The Mausoleum was constructed on an octagonal base, topped by a dome. The octagon symbolized the transition from earth to heaven, with the eight points representing the solstices, equinoxes, seasons and cardinal and intermediate directions. The present octagonal roof is a later addition. When the Mausoleum roof was renovated, laser investigations showed that the original cupola had been lower and rounder with a circular opening (oculus) at its centre. The open oculus would have allowed the sun to play over certain parts of the Temple, particularly over the images in the frieze and probably over the space designated for Diocletian’s sarcophagus.
The significance of sunlight shining through an oculus has been demonstrated in the Villa Adriana at Tivoli and the Pantheon in Rome in recent years. As the oculus was such an important feature in the symbolic link between earth and the heavenly sun, it is likely that at least one of the round temples in Diocletian's temenos was also open to the sky.
THE VESTIBULE
The one structure in the Palace which has retained the open oculus in its dome is the Vestibule. This structure stood behind the Protiron, in line with the Peristyle and the Porta Aurea.
The function of the Vestibule has not been established. It is generally considered to have been a kind of lobby, leading into the Aula or Salutatorium. It had a circular ground plan, and was enclosed at ground floor level by square walls. Cylindrical structures in the spaces to the sides of the northern doorway, between the rounded sides of the Vestibule and the squared enclosing walls, suggest that there may have been machinery, probably water-operated, to open and close heavy doors. These would probably have been bronze, constituting the Porta Aenea. Bronze represented Mars, the god of war, and victory over enemies. It is possible that these doors formed an ‘ad Calchi’, as in the Palaces in Ravenna and Constantinople, a term connected with the cult of the Emperor trampling on his subjects to make them well, or trampling on his enemies to subdue them.
The Vestibule was richly decorated with mosaics, fragments of which have been found. The interior of the dome was described as shimmering in gold by Marko Marulić (1450 - 1524), who referred to it as a fifth temple. In 2003 and 2004, Mladen Pejaković demonstrated the play of the sun’s rays over the interior of the central northern niches during the solstices and equinoxes, leaving no doubt that the building had a significant symbolic role, and was not roofed over.
CONCLUSION: THE PALACE AND ITS SACRAL PURPOSE
The Palace at Aspalathos was carefully designed to combine the earthly and the spiritual. While the northern section was probably planned for practical activities including administration, the southern part comprising the Temenos and Imperial Quarters formed a hallowed sanctuary where the gods were revered alongside Diocletian the demi-god.
The structures of the Palace are imbued with symbolism relating to the gods. Specific use was made of the effects of the sun’s rays. The temples in the sacral area were designed as an image of the pathway from earth to heaven, with special emphasis on the Emperor’s destiny to take his place among the gods after death. It is perhaps ironical, or perhaps just, that after his death Diocletian’s Mausoleum became a shrine to St. Doimus, and its Crypt to St. Lucy, two Christians martyred in his purges.
Diocletian only enjoyed living in his Palace for some ten years. Even his remains were not allowed to remain in their allotted place. As he had no heirs, his personal connexion with the Palace ended with their removal. But a significant part of his creation has endured for centuries as a kind of monument imbued with many of its founder’s characteristics. Its defensive walls have never been forcibly penetrated by an enemy. Some old Split families, such as Skočibučić-Lukaris, Grisogono and Cipci, have been resident within the central part of the Palace for several centuries.
Historians, archaeologists and tens of thousands of tourists have found much to wonder at in the old structures. Little by little, the Palace’s deeper meaning and true purpose are being revealed, putting paid to the long-held image that it was planned as a luxurious retirement home for a humble retired emperor quietly tending his vegetable patches.
© Radoslav Bužančić and Vivian Grisogono 2015
Updated January, February, March 2016
Radoslav Bužančić is Chief Conservator at the Ministry of Culture Conservation Office for Split-Dalmatia County
An edited version of this article was published in 'Current World Archaeology' issue 71, May 2015
Some of the findings relating to Diocletian's Palace were presented by Dr. Bužančić in a lecture at the Georgian Society building in London on 19th November 2014
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