The palate of Dioclétien is the strengthened imperial residence built by the emperor Dioclétien on the Dalmatian coast to withdraw there after its voluntary abdication in 305. It is one of the buildings of the late Antiquité best preserved and the vestiges are preserved by it in the historical heart of Split, in Croatia, city which owes its Greek name at the end , Aspalathos indicating a white bush and not at the end Latin meaning palate.

A retirement for Dioclétien

The plan and vestiges of the palate

The residence of Dioclétien combines the aspects of several types of constructions: it is at the same time a fortress by its ramparts, a city with its streets and its sanctuaries, and a large villa by the luxury of its private apartments. It is thus representative of the three principal architectural forms which characterize the time of its founder.

The site on which the palate is built knows a double slope, with an uneven superior with 8  m, of north in the south, towards the coast, and lower than 2  m in the East-West direction. The built surface is higher than 3,8  ha and form a slightly irregular rectangle: dimensions external and interior on each side are thus respectively of 215,5  m and 191,25  m for the east and the west, 175  m and 151  m for north, and 181  m and 157,5  m for the south. As an indication, the palate occupies thus approximately 1/6e surface of a Forteresse legionary standard conceived for 5400 soldiers, and twice the surface of a fort of 500 auxiliaries. In 1926, date on which the medieval and modern habitat installed in the fortress still existed, the population will intra muros was of 3200 inhabitants for 278 houses.

Ramparts

Walls of the fortification, an average thickness of 2,10  m, consist of two facings of masonry, 0,40 with 0,60  m thickness and a solid mass of blocking - formless hardcores drowned in mortar. The facing external of the ramparts is an pseudo-isodomic rectangular apparatus of limestone breeze blocks carefully drawn up and assembled, without mortar, but with iron cramps. Masonry continuous without sat brick adjustment. It rests directly on foundations posed on the rock substrate.

The rampart becomes less thick in its upper part - 1,15  m - which begins two sitted under the embrasures of the windows of the covered way. Those are in the shapes of arcs made of two thinned down hardcore rows (outside of 17, interior of 11), of an average width of 2  m for 3,10 with 3,90  m height in the center. Simple a Corniche in S makes the turn of the perimeter to an regular interval of the ground, and thus, being given the slope, with a variable height: it is thus higher of 1,10  m with the north-eastern angle that with the western Door, the place low where it is still visible. On the west coast, the cornice is thus located at 22  m with the top of the sea level, but on the east coast, it is 0,82  m lower: the change of altitude is done with height of the octagonal tower of the northern Door. It results a difference in size from the openings of the covered way between the two western halves and is northern rampart - they are respectively of 3,60 and 3,10  Mr. Between each turn, one finds 6 or 7 openings.

The monotony of the galleries of frontage is stopped by three Loggia S,

The Peristyle

The cardo is prolonged in the south of the crossroads with the decumanus by a paved oblong court, bordered of arcade S, and measuring 27  m length for 13,50  m broad: a long time known under name “Court of the cathedral”, one took the practice at the 20th century to indicate it under the name of Péristyle, in reference to the two colonnades which delimit it. High of 5,25  m, the column S are in red Granite of Egypt for twelve of them, and out of marble for the others - perhaps in Cipollin of Eubée. Much of them had to be ringed of Bronze for a long time because they had fissured under the weight of the Architrave and of the arcades. More than one monument in itself, the Peristyle is actually made up of the frontages of the three monuments which border it, the monumental hall of the private apartments in the south, the porch of the Mausoleum in the east, and the frontage of the téménos of the Temple of Jupiter in the West.

In the beginning, the entrecolonnements of the side arcades were closed by a made Balustrade openwork panels (of the Transenne S), a height of 2,40  m: one of the transennes was still visible at the time of Adam. Entrecolonnement marking the entry of the Mausoleum and the téménos is slightly more important, while the three arcades more in the south are a little higher, until touching the architrave almost.

The southern part of the Peristyle corresponds to the porch monumental Tétrastyle of the private apartments: four columns of red granite surmounted by capital X Corinthian support a pediment and an architrave of which the central part, above the door, forms an arch. The pediment is surmounted in its turn of a broad plinth of 4,26  m having to accommodate a sculptor group - perhaps a Quadriga. The access to the porch since the court was done by two flights of steps leading to the side openings, while the entrecolonnement central one was barred by a transenne, giving him the shape of a court. It was thus not preceded by a rising staircase, but contrary to a staircase going down towards an arched door giving access at the lower level from the Hall, and with beyond to the southern Door. To the Rebirth, two small vaults were added in the side entrecolonnements of the porch.

The level of the paved yard was in the beginning lower than that of the close monuments: it was thus surrounded by three degrees out of the three sides north, is and western. Taken as a whole, the Peristyle is thus presented a little as a traditional temple which would have been completely turned over.

The Mausoleum

The Mausoleum occupies the south-eastern angle of the palate, a closed rectangular zone of 32  m broad for 39  m length, whose frontage is the arcade is Peristyle. The three other sides of the enclosure are blank walls, of the same height than the arcade, comprising in the interior facing of the niches alternatively of semicircular and square form, where were to be installed statues. The central space of this téménos is occupied by the octagonal Mausolée of Dioclétien, the monument best preserved palate, mainly thanks to its later transformation into church and with its restoration between 1880 and 1885.

The Mausoleum is a Octogone of 7,60  m on side of which thick walls of 2,75  m thickness rest on a broader podium, high of 3,70  Mr. the podium, also octagonal, shelters a Crypte arched 13  m of diameter, and is prolonged towards the west on approximately 9  m to support the porch of entry. It is on the south-western side of this extension that is the narrow opening (approximately 1  m) of a passage giving access the crypt by the west coast. This crypt, which enlightened and was aired by three slits located close to the top of the podium, probably did not have a formal function, and could not be the place of rest of the Sarcophage of Dioclétien. The interior was decorated with it and partly not blocked by eight buttresses projected in front of the walls towards the center. The existence of a well, whose date is not certain, lets think that this space remained accessible, although its function is not clear.

The interior space of the téménos, around the Mausoleum, could be paved or arranged in garden. The entry of the Mausoleum itself, on the west coast, is announced by a continuous Chambranle, richly decorated with a rinceau with vine strewn with heads with animals. Two console S support a crowning in plank. Almost all the original porch of entry disappeared following construction from the Beffroi between the 13th century and the 17th century: one preserves in his foundations only the traces of the eight columns of the porch, which was to resemble a smaller version of the porch of the Hall.

The circular room of the Mausoleum has a diameter of 13,35  m for a maximum height of 21,50  m, in the center. On the level of the ground, the sides are occupied in alternation by four semicircular niches and four rectangular niches - of which one corresponds to the entry on the west coast. Between the niches, at a distance from 0,56  m of the wall, are eight red granite columns of Assouan, surmounted by a Corinthian capital, and an architrave with setback, which give to this great order a total height of 9,06  Mr. It is in his surmounted turn, without base, of a small order including/understanding eight columns - four of porphyry and four of gray Egyptian granite - four composite capitals and four capitals néo-Corinthians, and a second architrave with setback, for a height of 4,85  Mr. the two combined orders reach a height, at the base of the Coupole, of 13,91  Mr. the columns do not have an architectural function, but are purely decorative and were added after the completion of the structure of the Mausoleum.

The hemispherical cupola rises with a height of 1,25  m with the top of the higher cornice. It is made bricks produced locally, carrying stamp DALMATI. The masonry of the Voûte presents a double system, with a construction let us trompillons some staged for the lower part (who gives to the facing a reason similar to a plumage - to see the illustration opposite), and a construction in conical sections for the upper part. She was not bored of a oculus , contrary for example to the Coupole of the the Pantheon of Rome. Masonry was probably hidden by a mosaic coating of . The cupola was covered by a tiled roof to eight slopes, surmounted by a pine cone resting on four animal figures.

The ground of the room was paved at the black and white marble origin. The provision of the funerary installations of Dioclétien and its family in this space is not known. The historian Ammien Marcellin brings back in 356 the flight of a dress of crimson being in this tomb. In addition, the sarcophagus of Dioclétien was probably out of porphyry, as it is the case for those of the dynasty constantinienne: porphyry fragments preserved at the archaeological museum of Split could come from it.

Only the other original decoration having survived is a plank carved behind the capitals of the higher order: they are scenes of hunting, with Érotes, garlands and masks. Érotes carry crowns in which three faces are carved which point out the decoration of some Roman sarcophagi. Above the niche facing the entry, two busts, one of man are, the other of woman, respectively identified in Dioclétien and with its Prisca wife, who never accepted the dignity of augusta nor was not officially recognized like empress. A third portrait corresponds to Hermes Pyschopompe.

The Mausoleum is surrounded by a gantry of 24 columns in re-employment, various materials, bearing of the capitals Corinthian, and covered by a roof of tiles resting on an architrave on the exterior facade of the Mausoleum.

The Mausoleum of Dioclétien is comparable with other contemporary monuments such as the Mausolée of Galère to Thessalonique, and especially the Mausolée of Maxence on the Via Appia with Rome. It is in any case one of the monuments of late Antiquity best preserved.

The Temple

The south-western angle of the palate was occupied by another téménos, of a width equivalent to that of the Mausoleum, but longer (44  m). It included/understood a small traditional temple and two circular structures, in the north-eastern and south-eastern angles, perhaps corresponding to furnace bridges. These the last two buildings are preserved only at the state of foundations and their function cannot be identified with certainty.

The temple is a tetrastyle building prostyle Corinthian, the entry turned towards the Peristyle, and built on a podium of 21  m on 9,30  m, for a height of 2,50  Mr. It remains nothing the Pronaos and thus the frontage, but the remainder of the temple is very well preserved. The walls external of the concealed, long 11,40  m, present an apparatus well adjusted, and are decorated with the angles with pilasters with their capital. The door, broad of 2,50  m and high of 6  m, has a richly carved casing: in the middle of the foliage, children gather grapes while birds flutter around. Two console S with Volute S support a Corinthian cornice with ten Modillon S: let us entremodillons are occupied by carved heads accounting for two tritons, Hélios, Héraclès, Apollon, a not identified human head, two Victoire S winged and an eagle. No element of this iconographic program can be directly connected to the tetrarchic ideology.

The room of the temple is covered by a barrel vault, made of three lines of flagstones carefully adjusted, and carved to form a coffered ceiling: the carved decoration of human heads and Rosette S is often compared by it with that of the temple of Venus in Rome, built under the reign of Hadrian close to the Forum romanum. Immediately under the vault runs a Corinthian cornice gift' T modillons them are decorated by flashes.

The statue of worship which contained concealed it is probably that which was carried with Venice at the end of the 14th century: it is supposed, according to the divine ascent that Dioclétien wanted to be given, that it was about a Jupiter statue, to which would have been dedicated the temple. The presence of the eagle jovien, and the heroic Jupiter servant which is Héraclès among the carved figures of the external cornice, but also that of the flashes on the interior cornice agree well with this assumption.

Like the podium of the Mausoleum, that of the Temple comprises a crypt, which one reaches by a narrow passage the back. Its function is unknown.

The Hall

Behind monumental porch of entry constituting the southern part of the Peristyle is the Hall, a large circular room (Rotonde) of 12  m of diameter and 17  m height. Its walls do not present an apparatus of drawn up breeze blocks but a masonry alternating bases of hardcores and mortar and those of bricks ( opus incertum mixtum ). Four semicircular niches open on both sides entries north and south of the part, which was enlightened at the origin by small high windows. The ceiling is a vault which, like the walls, was to be covered with a mosaic of coloured glass. The rotunda of the Hall is registered in a square building, so that the walls were sufficiently thick in the angles to allow the installation of staircases in spiral leading to the levels superior and inferior. The level in basement of the Hall was equipped with access on its four sides, towards the thermal baths is and western, the Peristyle and the basements of the apartments.

Thermal baths

The narrow band of space located between the two téménos at north and the private apartments at the south is occupied by two small thermal units, having each one them Palestre and their parts of services. These two baths were discovered only by the contemporary excavations and remain badly known. Several parts equipped with Hypocauste S were identified as well as a Praefurnium for the western baths.

The water supply of these thermal baths and the whole of the palate is done by a Aqueduc bringing the water of Jadro, distant river of 9,7  km. The section best preserved this primarily underground work includes/understands 28 high arches of 16,5  m crossing the valley dries of Dujmovača. The flow of the aqueduct is estimated at 13 m/s. that is to say 1  000  000  m per day.

Private apartments

The residential zone itself of the palate corresponds to a band of 40  m broad immediately behind of the southern frontage. These apartments rest on a whole of arched underground parts a height which can reach 8  Mr. the main entrance is in the prolongation of the southern passage of the Hall, with a large rectangular part (31 X 12  m) in the architectural continuity of the Peristyle. This part, lit by high windows, was perhaps covered with a barrel vault, and connected the Hall to north with the long gallery of the southern frontage, the only access to the private apartments.

Two wells of light flank the hall and separate it from two symmetrical lines of small rectangular parts (approximately 4,30 X 5,25  m), covered with barrel vaults, and opening on a corridor arched on the opposite side. In half is, are a whole of well of light and parts ordered around a large octagonal part equipped with niches, where one admits room-with-eating it principal, the Triclinium . The North-South axis of this part corresponds to the entries and is about aligned with one of the largest openings of the southern frontage of the palate. The western half of the apartments includes/understands more the big room, of rectangular form (32 X 14  m), finished at the northern end by a Apse registered. Its vaults in crossing rest on six massive pillars laid out in two lines creating three distinct wings. The part is lit by two symmetrical wells of light on the east coasts and west. One reaches it by three doors on the southern part. It is probable that it is about the principal courtroom of the palate. The western end of the complex is occupied by a whole of 14 small varied pipe fittings, some equipped with apses, other circulars or cruciform. The localization of this whole close to the courtroom and triclinium suggests that they are the properly privative parts of the residence.

The interpretation of the complex: imperial palace, fortress or villa?

The denomination of “palate” commonly allotted to the architectural complex of Split can be misleading: while abdicating formally, Dioclétien became again an ordinary citizen, and it is as such as it spends the last years of its life in this residence, that the contemporary sources indicate without possible ambiguity like a villa . It there has thus not testimony that monument has served as Palatium (the Latin term which is the etymological origin of “palate”), i.e. of building designed at the same time to shelter the imperial private residence and to deploy the developed ceremonial aulic which characterizes the imperial capacity in late Antiquity.

Split and the theory of the imperial palace

However, the first architects and archeologists to devote developed studies of Split recognize there readily architectural characteristics which announce according to them the plan of the late ancient imperial palaces and Byzantine: the importance of the ways with colonnades, the Peristyle and its monumental porch, the Hall, inter alia, resemble the halls, rooms of reception, rotundas and basilicas which one finds indeed in the later imperial palaces. The risk of this interpretation is that of a double anachronism, in the history of the imperial ceremonial on the one hand, and in the course of the life of Dioclétien on the other hand - he is not any more emperor when he occupies this residence and its attested main activity is not the government but the gardening!

The architecture of the complex of Split was brought closer to other contemporary constructions: Dioclétien thus built a true palate, at the time of its reign, with Antioche, which is known only by description that the speaker Libanios left some: the apartments were at the end of a street, behind a monumental porch, while one of the frontages gave on a water level and had a colonnade and loggias. The monumental porch of the Hall in the Peristyle can also evoke the frontage in background of the Missorium de Théodose, sometimes identified with the imperial palace of Milan. These bringings together led certain historians such Ejnar Dyggve to recognize in the plan of Split a complex ceremonial ordered along a driving central axis in the imperial courtroom: the first element would be the Peristyle interpreted like a basilica with open sky, with the threshold of which appears the emperor within an architectural framework underlining the majesty of his person - the porch of the Hall - right in front of the throne room itself - the Hall thus reinterpreted, by underlining the cosmic architectural symbolic system which its cupola would constitute.

The bringings together are nevertheless misleading. The number of imperial palaces tetrarchic, or chronologically close relations, sufficiently known to be included in the reasoning specialist in comparative literature is very weak: there remain nothing the palate of government of Dioclétien which was with Nicomédie, and practically nothing the palates Sirmium, Milan or Trier (put aside the basilica in this last case). The vestiges of the Large palace of Constantinople are almost also thin, and the reconstitutions tried on the basis of description which remains about it vary considerably. The description of Libanios for that of Antioche does not say anything of its internal organization. The only rather well-known example which could be quoted is the Palais of Galère in Thessalonique: but this complex is fully integrated into the town planning of the tetrarchic capital, in particular via the Arc of Galère and the Hippodrome, and consequently is absolutely not comparable with the architectural whole of Split, built in full shift.

All the quoted elements as characteristic of late architecture palatiale ancient can actually be allotted to other architectural models much more widespread: the frontage with gantries is not a symbol of authority but a feature common to almost all the public edifices; the use of main street to colonnades in an orthogonal plan meets in all the big cities of the Roman East; the strengthened perimeter is distinguished from the urban enclosures of the time. Even the description of the porch of entry of the palate of Antioche is not really comparable with the Peristyle: in the first case, it is indeed about the main entrance of the complex palatial since outside, whereas in the second case, it is an interior entry with the complex.

The Peristyle does not have besides the function of a basilica, but of a space of communication, a crossroads articulating between them the various monuments (Temple, Mausolée) and especially the various levels of the palate: the staircase going down to the basement from the Hall and thus connecting the Peristyle to the gallery of frontage and the southern door is for this reason the architectural element determining. Structural continuity between the Peristyle and the private apartments exists well, but it must be interpreted in terms of circulation and not according to the model of an imperial processional ceremonial. It should not make forget the difference in levels: the private apartments are thus raised to remain on a level comparable with constructions of the northern part of the complex, and to thus compensate for the angle of rest.

A fortress?

By certain aspects the complex palatial recalls the military architecture of the period: the overall plan itself evokes that of a rectangular Castrum , model which Tétrarques build of number on the borders of the empire. The fitting of the streets is similar to that of a Roman military camp: the via praetoria leads northern Door ( carried praetoria ) to a crossroads with the via principalis connecting the doors is and western ( carried principalis will dextra and will sinistra ). It is beyond this junction that one normally finds in a fort the Principia , the general headquarter, flanked by the Prétoire ( praetorium ), the residence of the commander of the garrison, and the sanctuary ( aedes ) of the ensigns legionaries.

Among the variations from this point of view known for the time, one thus finds the fort of Drobeta, on northern bank of the the Danube, where space is divided into four symmetrical districts by the two perpendicular center lanes, or, nearer still to the diagram of Split, the fortress of Dioclétien with Palmyre: one finds there the same fitting of the ways while the principia are located against the interior side, contrary to the principal door. The comparison is valid only if one recognizes elements of principia in the buildings of the southern part of the palate of Dioclétien to Split: for this reason, the Peristyle with its colonnade and its monumental porch with central arc can evoke the frontage of a aedes principiorum of a fortress traditional legionary.

With its characteristics borrowing at the same time from the military architecture, urban and residential rural, it is in fact, to take again the expression of NR. Duval, the equivalent of a modern castle. But just as the voluntary abdication of Dioclétien was an amazing fact of the Roman imperial history, the residence planned for its retirement remained a building without true equivalent.

The palate after Antiquity

The Archevêque Jean of Ravenne ironically transforms the mausoleum of the persecuting large last of Christianity (with the Galère emperor) into church cathedral of Split.