RIHA Journal 0245 | 8 June 2020
A Symbol of Habsburg Military Power: the Slavonian General Command Palace in Osijek (1723)
The Palace of the Slavonian General Command in Osijek was built in 1723–1724 for the needs of the administration of the Slavonian Military Frontier, formed after the Karlowitz Treaty (1699). In keeping with its preeminent purpose as the seat of the Imperial War Council representatives, the palace stands out with a richly diversified exterior accentuated by a portal with atlantes, and a complex interior organized around a three-aisled vestibule. This gave it an outstanding position in the context of kindred administrative buildings in the wider Central-European region, indicating that the origins of the design were in the Baroque architecture of Vienna. The project itself emerged from the circle of military architects engaged in work on the border fortress cities of the Habsburg Monarchy, whose fortification was supervised by Eugene of Savoy, as President of the Imperial War Council.
The Palace of the
Slavonian General Command and the fortress city of Osijek
Architectural characteristics of the Slavonian General Command Palace
The design and construction of the Slavonian General Command Palace
The origins of the project and the Central-European context of the Slavonian General Command Palace
On vestibules with columns
On portals with atlantes
On the question of attribution
 The Palace of the Slavonian General Command in Osijek,1 today the seat of the Josip Juraj Strossmayer University, was built in the 1720s for the administration of the Slavonian Military Frontier. The great war of liberation from the Ottoman Turks, in which Prince Eugene of Savoy played a key role, began with the Ottoman defeat at Vienna (1683) and ended with the Treaty of Karlowitz (1699). After it ended, the liberated territory of eastern Croatia (Slavonia, Baranja, Srijem) was excluded from the jurisdiction of the Croatian Kingdom and placed under the Court Chamber in Vienna, while the Imperial War Council took over military control. This territorial organization led to the construction of an integrated system of fortress cities and the establishment of general commands; in view of the order in which territories were liberated, the Slavonian General Command was founded first (1701). Its seat was in the city liberated first – Osijek (1687), which had a prominent strategic position on the south bank of the Drava. Parallel with the fortification of Osijek, which got a modern system of bastions, and the transformation of its medieval tissue into a planned Baroque town, plans began to build the Palace of the General Command on the central square. This palace was to house the offices of the Court Chamber and the War Council, and serve as a residence for the Commander of Slavonia (Figs. 1, 2).
 In accordance with its prestigious purpose, the palace is notable for distinctive architectural features – a richly diversified exterior accentuated by a portal with atlantes, and a complex interior arranged around a vestibule with columns. This makes it not only one of the finest Baroque palaces in Croatia, but also prominent in the framework of Central-European secular architecture.2 Moreover, in the context of the other general command headquarters on the territory of the Habsburg Monarchy bordering with the Ottoman Empire, which were erected in the period when the frontier was being restructured in the first half of the eighteenth century, the Osijek palace played the role of a prototype. Nevertheless, it was mentioned no more than incidentally in existing scholarly literature, the history of its construction is unexplored, and attribution and evaluations remain incomplete.3
 The institution of the Slavonian General Command was already established two years after the Treaty of Karlowitz.4 However, in those still uncertain times at the turn of the seventeenth to the eighteenth century the situation in the Osijek fortress city (known as Tvrđa) was such that the focus was on building fortifications; therefore, the General Command headquarters had at first to be placed in a temporary site. Archival plans – projects for the construction of the fortress and the town – show, however, that from the outset the most eminent city location had been reserved for the General Command Palace, on the spacious central square.
 When it was liberated from the Ottoman Turks in 1687, Osijek still retained its organic medieval urban tissue in which churches had been replaced by mosques during the 150-year-long Ottoman occupation. This is how it appears on the first plan for modernizing the fortifications from 1688,5 commissioned by the military commander Margrave Ludwig Wilhelm of Baden-Baden (1655–1707).6 Just two years later, the same military commander commissioned a new, considerably more radical plan from the chief fortification engineer for Hungary, Matthias von Kaysersfeld, which did not include only the bastion fortifications, but also an orthogonally planned city within them.7 Kaysersfeld's expertise on the basic principles of Baroque town planning is evidenced by the axial composition, in which the main communication passes through the central square, connects the 'land' and 'river' gates, and continues across a bridge over the Drava river to the Baranja plains. Crucial for our topic, though, is the planned building of the military command headquarters on the central square. When he came to Osijek in 1690, and devoted himself to the demanding work of reconstructing the town and fortifications, Kaysersfeld had to somewhat modify the intended ideal symmetry of the urban matrix,8 as his new plans dated 1691 and 1693 show.9 The city centre, however, persisted on the square of Paradni trg (German, Paradeplatz), today’s Trg Sv. Trojstva (Holy Trinity Square), on which the General Command Palace was erected about thirty years later.
 The intensive development of the Osijek fortifications and of the planned town within them continued after the Karlowitz Treaty (1699), when Prince Eugene of Savoy (1663–1736) was appointed key organizer of the frontier defences.10 Becoming the head of the Imperial War Council in 1703, Prince Eugen began a radical modernization of the fortified border towns and carefully selected their commanders and engineers. In 1710, he sent a new commander to Osijek, General Johann Stephan von Beckers, who until his death in 1721 headed the construction of the fortress according to the Prince's instructions. He was succeeded by his son-in-law, General Maximilian Petrasch.11 In keeping with his fascination by Vauban and French fortresses, Eugene of Savoy ordered the designs from first-rate French and Swiss military engineers, outstanding among which were Jean Petis de la Croix and Nicolas Doxat de Démoret (1682–1738).12 The chief engineer, who supervised the construction of the fortifications and the town of Osijek for many years, however, was Johann Friedrich von Heisse (Heyß).13 Thanks to their activities, by the 1720s Osijek got a complex star-shaped surround of bastions reinforced with hornwork in the east and crownwork in the north, across the river Drava (Fig. 3).14
 Within this fortified surround the projected orthogonal town, which Kaysersfeld's plans show only in contours, grew into a Baroque setting, with large housing blocks, barracks built along the boundaries, and two religious focal points – a Jesuit College with the Church of St. Michael in the west, and a Franciscan Monastery with the Church of the Exaltation of the Holy Cross in the east.15 The most striking Baroque features, however, were given to the central square of Paradni trg with its stately public administration and military buildings, from the Magistrate Building in the east (1702) to the Main Guard in the west (1728), and its central accent, the Baroque Holy Trinity Column.16 But the finest building, not only on the square but in the whole town, is the Palace of the Slavonian General Command, which occupies an entire block on the north side of the square (Fig. 4).
 In its present form, the former Slavonian General Command Palace is a three-storey building with an inner courtyard.17 In its four-wing floor plan, the south front wing stands out as wider and more complex, with two rows of rooms – a row of wider rooms along the outer façade and a row of narrower rooms on the inside, and with a corridor (gallery) running along the courtyard side (subsequently removed).18 The somewhat narrower lateral wings have one row of rooms along the outer façades and a corridor (earlier a gallery) running along the courtyard side. The north, rear wing, the narrowest and originally the lowest (with then only a ground floor and an attic space; today it also has three storeys) has one row of rooms (Fig. 5).
 The ground floor of the front wing features a centrally placed, elegant, cross-vaulted vestibule (Figs. 6, 7) that passes through the entire width of the wing and is accessed through a portal. The axial nature of this composition is echoed in the appropriate positioning of the porte-cochère in the rear wing of the palace. The front part of the vestibule broadens into two 'side aisles', separated with stone Tuscan columns (two pairs) and corresponding semi-columns on the walls. The typically Baroque dynamic of this composition is complemented by the scenic arrangement, in the back part of the vestibule, of two symmetrically-placed, two-flight staircases that rise behind the lateral broadenings of the vestibule and lead to the first-floor lobby. The front end of the vestibule is flanked by square rooms with shallow sail vaults, while the flights of the staircases continue into small, cross-vaulted rooms. Cross vaults also appear above the staircase landings, and in the ground floor of the lateral wings.
 On the high first floor (piano nobile) the central zone is emphasized with a hall above the three-aisled part of the vestibule, opening onto a balcony above the portal. The lower second floor also used to have a central hall. In all the three floors the rooms in the front and side wings had communicating doors placed in line with each other – enfilade, and communication among them was improved by the courtyard corridor – the gallery. There are narrow, two-flight staircases at the ends of the two side wings. The rear wing has rooms of varying sizes, among which only those on the ground floor, with barrel vaults penetrated by lunettes, follow the original disposition, while the upper floors in that wing are entirely the result of recent additions.
 Not only the original floor plan, but also the interior Baroque arrangement and fittings have been partly preserved – the columns in the vestibule already mentioned, pilasters and mouldings in the staircases, as well as the ornate stucco featuring cartouches, volutes and lambrequins that adorn the arches and vaults in the vestibule, staircases and front rooms in the ground floor.19
 The palace exterior has uniform façade articulation, graded by the varying degrees of importance of the wings, with the main emphasis on the south-facing entrance façade (Fig. 8). The basic articulation is the profiled base and stylized rustication on the ground floor above which, on the upper floors, rise two superposed rows of Tuscan pilasters separated by a profiled string course. The façades are also broken up by the use of two colours of plaster – pink for the ground-floor rustication, cornice, string courses and pilasters, and white for the rest of the façade. The corners of the building are decorated with alternating rectangles painted pink.20
 The south, entrance façade is fifteen window bays wide, with logical emphasis on the central zone, as an expression of axial spatial organization. The central bay is not only wider but has a magnificent portal on the ground floor, superposed by a balcony and by double rectangular openings on the higher floors – balcony doors, and windows. The stone portal (Fig. 9) features atlantes flanked by composite columns and half-columns – bearers of the first-floor balcony. Rising from herm pilasters, the atlantes lean slightly toward the arch of the portal, supporting the balcony floor with both hands. This is also supported by a central bracket that rises from the keystone of the portal’s arch.The atlantes are cloaked with lion skins, which shows that this is in fact a combination with the mythological figure of Heracles. The herm pillars are decorated with the typically Baroque lambrequin motif, shallow vegetable motifs decorate the surfaces of the portal along the extrados, and the central bracket is particularly fine, with volutes, garlands and a mascaron. The convex-concave shaped balcony floor with a stone balustrade enhances the overall richness and Baroque dynamic (Fig. 10).
 In keeping with the articulation of the front, stylized rustication frames the rectangular ground-floor windows. The large first-floor windows have shallowly profiled frames, accentuated with trapezoidal keystones and lateral scrolling consoles for the hood moulds. Their frames are additionally adorned with panels in the parapet zones, which only appear on the main façade. The frames of the smaller square windows on the second floor are somewhat simpler.
 The side façades are eleven window bays wide and repeat the same moulding and colours, while the rear wing is only arranged with unframed openings (Fig. 21).21 The inner façades overlooking the courtyard are also completely simple, which is the result of recent interventions.
 The analysis of the building’s structure clearly shows that the Slavonian General Command Palace has retained its basic eighteenth-century Baroque features, although it underwent considerable rearrangement during the nineteenth and twentieth centuries. To accurately reconstruct what had been designed and what has been executed, it is necessary to rely also on archival documentation.
 The earliest information about the headquarters of the Slavonian General Command in Osijek dates from 1705, when "instructions" for its construction were issued in Vienna,22 but the first building was located on the edge of the town, in the block next to that of the Franciscan Church (Fig. 4).23 By 1716, it was already in such a bad condition that the Imperial War Council requested its repair, having secured funding from the Fortifications Fund.24 Documents in the Vienna War Archives note that the Commander of Slavonia, Johann Stephan von Beckers, got instructions about how to repair the General Command building and that the plan, apparently made by one of the competent engineers, most probably Johann Friedrich von Heisse, had already been sent from Osijek to Vienna for approval in January 1716.25
 It is difficult to know the degree to which the project had been implemented. Five years later, after the death of Commander Beckers in 1721, due to whose long-lasting illness some problems arose in the functioning of the Osijek fortress,26 the General Command building was again in a bad state of repair. The task of its rebuilding, this time in an appropriate location on Paradni trg Square, was given to Beckers's successor General Maximilian Petrasch (1668–1724).27 He, too, was a close associate of Eugene of Savoy and was appointed to the prestigious position of Commander of Slavonia after gaining distinction not only in warfare but also as head of construction of the fortresses in Slavonski Brod and Stara Gradiška.28
 Details about the beginning of construction of the General Command Palace in Osijek are to be found in newly discovered documents in the Vienna War Archives.29 These are correspondence between Maximilian Petrasch and the Imperial War Council,30 which show that Petrasch had already begun to organize the construction of the new General Command headquarters in the first year of assuming duty in Osijek. Namely, on 29 September 1721, he wrote to Vienna that after the plan for the "commander's house" is approved, preparations for its construction should be started in winter – felling trees and the construction of log cabins for a double brick kiln, and slaking lime in Srijem, which could be transported by boat.In addition, he worked out how many people would be needed to build the General Command Palace – thirty to forty masons in the first year, fifty to sixty in the second year, and after that, in the third and fourth years, as needed.31 Petrasch's letter of 16 November next year shows that the planned beginning of construction had not taken place in the previous year, because he wrote that "the mentioned apartment of the general or the commander is one of the highest priorities, because the old apartment is partially ruinous and without repairs it has started to collapse, and besides, it is so poorly furnished that no officer in the fortress has accommodation as bad as the commander’s, which substantially prevents him from performing his imperial service".32
 The above clearly shows that the architectural design for the General Command Palace was finished or nearing completion in September 1721 (its approval by the competent authorities in Vienna was expected), but that construction, despite Petrasch's insistence, had not even begun at the end of 1722. This is why the palace is not drawn on the report plans for Osijek in these two years, which the engineer Heisse sent to Vienna. Construction was obviously begun and completed in 1723, because in that year the caption on the plan of the Osijek fortress says the "building of the Generalate and the military commander's apartment" was placed under a roof (Fig. 3).33 There is reference to an enclosed attachment showing a drawing, most probably the architectural drawing itself, but this has unfortunately not been preserved.Therefore, putting off the beginning of construction was obviously made up for by rapid work on the imposing three-wing, two-storey, public and residential part of the palace. The works recorded next year relate to the construction of the ground-floor utility tract in the rear with stables, which closed the quadrilateral form of the complex along the northern side of the plot. General Petrasch’s report about "what was built last year  and what was begun and what could be done this year " only says in general "the commander's house", but the caption of the accompanying plan of Osijek details that "the foundations for the stables had been laid along the military command building".34
 Petrasch’s further management of constructing the General Command Palace was interrupted by his sudden death in 1724, so he and his family never even moved into the palace. Joseph Anton Count Oduyer (John O'Dwyer), of Irish extraction, Petrasch's successor in the post of Commander of Slavonia (1724–1729), took over supervision of construction and was the first general to move into the palace.35 The plans of Osijek show, however, that work on the palace continued even after it had begun to be used, under later commanders, all of them distinguished military leaders and aristocrats as Ludwig Andreas von Khevenhüller, Count of Aichelberg-Frankenburg (1733–1744), and Ascanio Guadagni (Quadagni) (1744–1750).
 In that period the interior was being furnished and the east wing was completed, as we learn from the 1731 plan of Osijek, which shows the northern part of the east wing as unfinished.36 The reason for the delay in work on that part of the palace could have been caused by the existing artillery barracks (built on that site in 1711),37 which could probably not immediately be completely removed. The data about the gradual completion of the eastern wing are confirmed by traces in the palace structure. In any event, the lists of work executed in 1747 and 1748 show that the east wing had already been built at that time.38
 Traces in the structure itself suggest that the second floor was added to the elegant three-wing part of the building somewhat later. Namely, the string course between the first and second floors juts out from the wall more than is usual for a string course, indicating that it had originally been the final cornice of the façade. The originally smaller number of storeys is also logical, since the 1720s, when the palace was built, were still a time of uncertainty that did not allow construction above the height of the bastion defence ring. It is also possible that the construction of the second floor was planned in the original design, but was only executed subsequently. The need for this enlargement could have resulted from the decision to house the Land Deputation (German, Landesdeputation) in the palace, which the Vienna Court founded in 1737 as provincial administration subordinate to the Court Chamber and the War Council.39
 The above-mentioned condition of the three-storey Baroque palace of the Slavonian General Command was fixed on drawings from 1765 (Fig. 11).40 This report showed the floor plans of the ground floor and both the upper floors, a longitudinal section through the central part of the front and rear wings, and the main façade. Based on this drawing, in earlier literature the addition of the second floor was dated to 1765,41 but if the accompanying captions and graphics are read and analysed carefully, it is clear that this took place earlier. The title of the plan says that the palace was in the "military year 1764/1765, by building a new roof, renewed and ready for occupancy, and the upper (second) floor was renovated to accommodate staff members".This is confirmed by the graphic interpretation of the drawing in which, in the manner usual at that time, red was used to mark what already existed, and the existing construction and the walls of the second floor are shown in red. Yellow, which marked new construction, was only used for certain partition walls on the second floor, the slight raising of its bearing walls, and the new pitched roof with small mansard windows lying in them.42 The conversion of the second floor into officers' accommodation is indirectly confirmed in the 1764 plan of Osijek, on which the General Command Palace, which had until then usually been referred to as Generalat Haus or Kommandanten Wohnung, was for the first time called Generalat Caserne, indicating that it also contained accommodation for a larger number of soldiers.43
 Along with revealing details about furnishing the second floor, the drawings from 1765 are also valuable for analysing the Baroque characteristics of the palace. In the first place, comparison of the drawings with the present status of the building proves that the floor plan of the palace and the design of the external façades44 have basically preserved their original appearance. In contrast, the volume composition, the appearance of the courtyard façades and the roof were considerably altered in recent interventions. Unlike today's closed, four-wing building of uniform height,45 the floor plans and the section show the palace as a structure of diversified volume with a three-storey, three-wing representative part (south front wing and side wings) and a northern, low, utility wing with a ground floor and attic space.The stages in completing the east lateral wing, mentioned earlier, have remained documented on the 1765 plan, which shows the second floor in that stretch as only partially constructed. As for the appearance of the interior façades, which are today completely plain, the floor plans show arcaded galleries with sail vaults, and the section confirms that Tuscan columns carried the arches.46 The Baroque quality of the palace was also greatly diminished by replacing the high, steep roof, that is shown, with a roof that is much lower and less steep.47
 The 1765 plans are also a valuable document for understanding the purpose of particular rooms. The apartment assigned to Johann Reichard Baron of Wolffersdorff, then a vice-commander in Slavonia, occupied the ground floor in the western side of the main south wing and in the entire west wing. The eastern side of the main south wing and the east wing served as a war office and an apartment for the keeper of the war records. The entire first floor was reserved for the apartment of the Commander of the Slavonic General Command: "his excellency the commanding officer, the marshal general".48 On the second floor were apartments for seven staff members and their families. In the north wing, the ground floor held stables situated on both sides of the central porte-cochère, which originally had a sail vault. To the north-west was a store for wood, and the north-east corner of the building was a store for carts. This wing had a relatively high knee wall to create additional attic space (for a hay loft). The courtyard had a well alongside the rear wing.
 The 1765 design faithfully shows interior furnishings, some of which are still preserved. Among those that are missing is the mirror vault with moulding and central stucco moulding in the first-floor hall, as well as numerous ornate tiled stoves. We can only speculate about the other elements of interior furnishing, but given that the palace was home to members of the Central-European nobility and that they used it to receive high political, military and other officials, we may assume that the living quarters were luxuriously furnished.49
 There was no need for any major architectural interventions on the palace and its arrangement until the end of the eighteenth century. The decline in the military importance of the frontier areas of the Habsburg Monarchy due to the weakening of the Ottoman Empire, and the accompanying reorganization of the military administration, resulted, however, in the gradual loss of its original functions. In 1774, the commander's apartment was moved to the Kostić House in today's Ulica Franje Kuhača 2350 (Fig. 4), which may have been because Emperor Joseph II arrived in Osijek that year and resided in the General Command Palace.51 Somewhat later, in 1783, the palace lost its public function when the military command headquarters were relocated to Petrovaradin.52 It was degraded to ordinary barracks in the nineteenth and twentieth centuries, which led to the deterioration of the building’s fabric. When the palace became the seat of the University of Osijek in the 1990s, it got back its public role and the process of gradual restoration began.
 The Slavonian General Command Palace has the essential features of a Baroque palace, these being a dominant position in the urban tissue, a free-standing multi-wing volume, and an axial internal organization with impressive spaces, such as the vestibule and hall, in the central axis, which also finds articulation in the design of the façade. It is not only the first palace of this kind on the south-eastern frontier of the Habsburg Monarchy, but is also an unprecedented architectural accomplishment on the wider territory of continental Croatia.In addition to the above, which we might call general characteristics of a Baroque palace arising from the stylistic development of the seventeenth-century palazzo in Italy, and especially in Rome,53 the Osijek palace also has some specific elements of design. These are the frequently-mentioned vestibule with columns and the front portal with atlantes. They greatly narrow down the possible origins of its design to the capital of the Habsburg Monarchy, Vienna, which controlled the development of post-Ottoman Osijek, and therefore also the construction of the Palace of the Slavonian General Command.
 After the Ottoman defeat at Vienna in 1683, Austria flourished politically and became a leading European power, and this also resulted in the burgeoning of Baroque architecture in its capital. The palace or the stately mansion was the main way for political leaders to express their power, primarily for a personage like Prince Eugene of Savoy and other aristocrats.54 The main visual characteristic of the Viennese palazzo was the inventive combination of the French plan and Italian articulation, the main architects were Johann Bernhard Fischer von Erlach (1656–1723) and Johann Lucas von Hildebrandt (1668–1745), and the main theme was the aristocratic palace, both the palace within the city walls as well as the suburban garden palace.55 However, the principal Baroque features in the spatial organization of Vienna’s aristocratic residences, reflections of which we find in the Osijek palace, were not innovations introduced solely by the aforementioned great Austrian Baroque architects, nor were they primarily reserved for privileged palaces.56 These features appeared in Vienna earlier, brought by a succession of Italian architects educated on the heritage of Roman architecture. These architects contributed to the Baroque transformation of the Habsburg capital and to the spreading of Baroque innovations to Austrian provinces and border areas, which included Osijek. It is this circle that launched the elements specific for our palace – the vestibule with columns and the portal with atlantes – which soon became a kind of hallmark for the most prominent Baroque palaces of Vienna.
 The division of entrance halls with columns, as a highly elegant element that enables separation into several aisles and was previously reserved almost exclusively for sacral buildings, is not, of course, a Viennese invention; it first appeared in Roman palaces, from the Farnese Palace (Antonio da Sangallo the Younger, 1515) to the Barberini Palace (Carlo Maderno, 1627–1629; Gian Lorenzo Bernini, 1629–1633), to mention only the finest.57
 In Vienna, the idea of a vestibule with columns was inaugurated in the Liechtenstein Garden Palace (Domenico Egidio Rossi, Domenico Martinelli, begun in 1690), although there the columns are not detached but lean against piers. However, it reached perfection in the city palace of the same family, with a 'forest' of monumental Tuscan columns (begun in 1692).58 The basic design was conceived by Enrico Zuccalli (1642–1724), an international-level architect, which also meant co-operation with Gian Lorenzo Bernini himself, while Domenico Martinelli headed the construction.59 Their efforts produced a magnificent, almost free-standing palace located on the very edge of Vienna’s historic core (Bankgasse 9), along the former defence wall, today's Ring.60 The special importance of the Liechtenstein Palace for the development of Viennese architecture arises from the successful creation of a monumentalized version of the front of Bernini's Chigi-Odeschalchi Palace in Rome, which was, thanks to Hellmut Lorenz’s research, clearly defined as the contribution of Zuccalli.61 Martinelli is attributed with the sculptural enrichment of the exterior, particularly expressed in the numerous fantastic mascarons above the ground-floor window architraves.
 The interior is dominated by a magnificent vestibule, which Tuscan columns divide into five cross-vaulted aisles (Fig. 12). The laterally placed, ceremonial, L-shaped staircase underlines the modernity of the spatial solution, although in this case there is no symmetrically positioned staircase on the opposite side because of constraints imposed by the size of the town plot. The scenic properties of the vestibule are enhanced by its opening into the atrium, and the Baroque idea of axial spatial organization is rounded off by the centrally-placed main hall, whose width corresponds with that of the middle-storey projection on the façade above the vestibule.