M anu scri pt M ap of I l l yri cu m , 1 663, i n the Ponti fi cal Croati an Col l eg e of St Jerom e: a Su ppl em ent to Previ ou s Knowl ed g e

. In the Pontifical Croatian College of St. Jerome in Rome, a manuscript geographic map of Illyricum is kept, drawn in 1 663 by the architect and geographer, Pietro Andrea Buffalini of Rome. Cartographic analysis of this map has been carried out on several occasions, and the ecclesiastico-legal and historico-geographic context of its origin analysed. As contribution to previous research on the 1 663 map of Illyricum, the depiction of the coast on that map is cartometrically compared with that on geographic maps and nautical charts from the late 1 6th century and the first half of the 1 7th. On the basis of these analyses it is confirmed that, with the 1 663 map of Illyricum, a qualitative step forward was taken in depicting the northeast coast of the Adriatic. In addition, on the basis of research into available written data sources, it is concluded that Ivan Lučić made a key (co)authorial contribution to the shaping of the geographic content of this manuscript map.


Introduction
In the Pontifical Croatian College of St Jerome, in Rome, a manuscript geographic map of the Croatian countries is kept, drawn in 1663 by the architect and geographer, Pietro Andrea Buffalini, of Rome.The map dimensions are 155 cm × 100 cm (the outer dimensions of the frame being 190 cm × 125 cm).It contains a display not of a graticule, but of a linear scale bar and a simplified display of the directions of north (marked by a stylized lily sign, commonly known as fleur-de-lis) and east (marked by the sign ofa cross) on a blue circle.Although the map has no title, its content and purpose are described in a cartouche: Congregatio Nationis Illyricae sicuti instituta fuit ab Illyricis ex Dalmatia, Croatia, Bosna et Slauonia in Urbem confluentibus; ita eorundem Regnorum Nationales tantum, vel Oriundi, Slavonica tamen lingua loquentes, iurium ipsarum participes esse debent: ut constat ex Decisione Sacrae Rotae diei X Decembris MDCLV coram R.P.D. Priolo: Ideo ad evitandas U Papinskom hrvatskom zavodu Sv.Jeronima u Rimu čuva se rukopisna geografska karta hrvatskih zemalja koju je nacrtao arhitekt i geograf Pietro Andrea Buffalini iz Rima 1663.Karta izrađena je u dimenzijama 155 cm × 100 cm (vanjske dimenzije okvira iznose 190 cm × 125 cm).Ne sadrži prikaz stupanjske mreže, već linearno mjerilo i pojednostavljeni prikaz smjera sjevera (označen stiliziranim znakom cvijeta ljiljana, poznat i kao fleur-de-lis) i istoka (označen znakom križa) na plavom krugu.Premda karta nema naslov, u kartuši je opisan njezin sadržaj i njezina namjena: Congregatio Nationis Illyricae sicuti instituta fuit ab Illyricis ex Dalmatia, Croatia, Bosna et Slauonia in Urbem confluentibus; ita eorundem Regnorum Nationales tantum, vel Oriundi, Slavonica tamen lingua loquentes, iurium ipsarum participes esse debent: ut constat ex Decisione Sacrae Rotae diei X Decembris MDCLV coram R.P.D. Priolo: Ideo ad evitandas aequivocationes vel fraudes KiG Spec.Issue, Vol.21 , 2022, https://doi.org/10.32909/kg.21.si.3 aequivocationes vel fraudes haec quatuor Regna, fines que eorum delineati fuerunt ut possint distingui quae loca includi, quaeue excludi debeant. 1 It is, therefore, a cartographic representation of four provinces -Dalmatia, Croatia, Slavonia and Bosnia -which coincide with the geographic name of Illyricum, and from which those who can make use ofthe rights ofthe Congregation of the Illyrian (Croatian) nation have the right to come into the pontifical college of St Jerome.It is the first known modern map showing all the large spatial units which were settled at that time by a Croatian population, those who use the Croatian language (Slavonica lingua) (Mlinarić et al. 2012).At the time of the creation of the 1663 map of Illyricum, the area shown was politically divided among three states: the Habsburg Monarchy, the Ottoman Empire and the Republic of Venice, and only the area of the Republic of Dubrovnik functionally practised a high degree of political independence.The map, however, does not reflect particular imperial interests and the narratives associated with them, but the awareness ofbelonging to the same ethnic or linguistic body, based on the ancient tradition framed by the Roman-era name of Illyricum.From a formal perspective, it is an anachronism, but also a functionally skilful choice of a name that made it possible to spatially encompass varying regional entities.This area is demarcated in relation to the neighbouring European regions by a border whose edge has the text Confini delle quatro prouincie Illyriche.Within this border, not all the areas that were then settled by Croats are shown.Specifically, Istria, Međimurje and the Croatian part of Baranja remain outside the borders.Ivan Črnčić, who was the first to briefly describe the map, offered a reason for excluding Međimurje: "Surely they were afraid ofthe town ofStrigov, where they claim that St Jerome was born" (Črnčić 1886: 69-70).In fact, even at the time ofthe creation ofthe map, there was a lively debate about the location of ancient Stridon, which lay, according to Jerome himself, on the border between Dalmatia and Pannonia, and it must have been difficult for advocates of Marulić's thesis that Jerome's Stridon should be the Sidron on Ptolemy's Fifth Map ofEurope to 'drag' Međimurje to that border (Bulić 1920, Suić 1986, Margetić 2002).
The 1663 map of Illyricum (Figure 1) is one of the oldest maps of the entire territory of today's Croatia, by which it is possible to precisely determine its utilitarian purpose and detect its users: determining the right to use the services of hospices, or institutes for Catholic Croats in Rome in accordance with the decree ofthe high judicial authorities ofthe Papal States to those who lie within the boundaries of the four provinces ofIllyricum: Dalmatia, Croatia, Slavonia and Bosnia.
Brief but substantive cartographic analysis of the 1663 map of Illyricum has already been carried out in the scientific literature (Črnčić 1886(Črnčić , Škrivanić 1968(Črnčić , Marković 1993)), and the ecclesiastico-legal and historico-geographic context of its genesis has also been analysed (Mlinarić et al. 2012).As a supplement to previous research on the 1663 map of Illyricum, the depiction of the coast on that map is cartometrically compared with that on selected geographic maps and nautical charts from the late 16th century and the first halfofthe 17th.On the basis ofthis analysis, we try to determine whether the selected maps served as templates for creating the 1663 map of Illyricum, and whether a qualitative step forward was taken with that map in the rendering ofthe northeast coast ofthe Adriatic.In addition, on the basis of research into the available written data sources, we try to contribute to the discussion on the (co)author's contributions to the shaping of the geographic content of the manuscript map ofIllyricum.
2 Authorship of the 1 663 Map of Illyricum Stjepan Gradić's contribution to the making of the map At the time of creation of the 1663 manuscript map of Illyricum, the head of the Fraternity of St Jerome in Rome was Stjepan Gradić (Stefano Gradi, Stephanus Gradius), from Dubrovnik (Krasić 1987: 92).In view of this, some scholars have logically believed that it was actually Gradić who gave Buffalini the necessary geographic data, and that Gradić was not only the legal representative ofthe client but also the creator ofthe map that was drawn, technically, by Buffalini.Moreover, Gradić's collaboration with Buffalini was very fruitful in other areas, too.Perhaps the most important achievement of this collaboration is Buffalini's engagement in the design of the new Dubrovnik cathedral, which, 1 Translation: As the Society of the Illyrian nation was founded by Illyrians from Dalmatia, Croatia, Bosnia and Slavonia who had gathered in the City (Rome), so only the peoples of those kingdoms who speak a Slavic language must be possessors of its rights: as follows from the resolution of the Sacra Rota Romana passed on 10 December 1655 before the venerable father Lord Priolus.Therefore, to avoid ambiguities (misunderstandings) or fraud, these four kingdoms and their boundaries have been depicted cartographically so that it might be determined which places can be included or excluded.(Bulić 1920, Suić 1986, Margetić 2002).Karta Ilirika iz 1663.(Slika 1) je jedna od najstarijih karata cijelog područja današnje Hrvatske kod kojih je moguće nedvojbeno precizno utvrditi njezinu utilitarnu svrhu i detektirati njezine korisnike: određivanje prava na korištenje usluga hospicija, odnosno zavoda za Hrvate katolike u Rimu po odredbi visoke sudske vlasti Papinske Države onima koji se nalaze unutar granica četiriju provincija Ilirika: Dalmacije, Hrvatske, Slavonije i Bosne.
In previous research, scientists started from the data that was first presented by Ivan Črnčić, writing about the problem of using the names Slovene and Illyrian in the guesthouse of St Jerome in Rome (Črnčić 1886: 69).The immediate motive for making the map ofIllyricum was a dispute over who could be a member ofthe College ofSt Jerome in Rome.In 1655, the Sacra Rota Romana ruled that Dalmatia, Croatia, Bosnia and Slavonia should be considered as Illyricum (Črnčić 1886: 64-66).The Fraternity of St Jerome in Rome ordered the creation of a map ofthat area on 6 October 1659, and the manuscript map was drawn up by the Roman architect Pietro Andrea Buffalini on 2 September 1663, for which he was paid 36 scudi.Črnčić added that during the creation of the map, the "painter" Buffalini was "directed" by the head ofthe Fraternity, Abbot Stjepan Gradić, ofDubrovnik, who was the curator of the Vatican Library and a member ofthe Academy ofthe Swedish Queen Kristina (Črnčić 1886: 69).
Gradić, in view ofhis position in the Fraternity ofSt Jerome, was unquestionably crucial in the choice of person who would draw the map.However, the question arises as to why Buffalini was chosen.Pietro Andrea Buffalini belonged to the academy of Italian artists in Rome under the title of St Luke (Accademia de i Pittori e Scultori di Roma), whose establishment was approved by papal breve in 1577.In the 1696 catalogue he is listed as Pietro Andrea Buffalini Architetto, and the date of his admittance to the academy, 16 June 1673, is noted next to his name (Ghezzi 1696: 51, Gudelj 2016: 193).Buffalini is also mentioned in the scientific literature as a professor of geography at Rome's University of La Sapienza (Bedini 2021: 281), which is also confirmed by a scientific treatise of the 17th century on the observation of celestial bodies, in which he signed himself "Io Pietro Andrea Buffalini Proffesore di Geografia mano propria" (Buffalini 1666: 38).
In Črnčić's wake, Gradić's contribution to the creation of the map was also highlighted by Gavro Škrivanić, stating that the map was created "in accordance with the ideas and instructions of Stiepo Gradić" (Škrivanić 1968: 273), while in another place he calls it "Gradić's map of Illyria-Dalmatia" (Škrivanić 1968: 276), which was "a first-class source for the historical and historicogeographic studies ofthat time" (Škrivanić 1968: 276).In the same way, the map has been attributed to Gradić by Ćosić and N. Glamuzina, repeating Črnčić's and Gavranović's statements that Buffalini made the map in accordance with Gradić's (Gradi's) instructions, calling that map "Gradi's map" (Ćosić and Glamuzina 2018: 207).Marković believes that it is not correct to refer to the map of Illyricum at the Croatian College of St Jerome in Rome, as Gradić's map, like Škrivanić did, "but it is a synthesis of the joint work of the members of the College with the cartographer Buffalini" (Marković 1993: 175-182, note 12).This was repeated by Slukan Altić, adding that Gradić and his colleagues "in creating the map, did not redraw existing maps, but each member of the College, with respect to their origins, participated in the mapping ofthat part ofIllyricum (Slukan Altić 2003: 130).
In support ofthis, one can highlight the fact that Buffalini, during the making ofthe map, resided at house no.17, owned by the Fraternity of St Jerome (Gudelj 2016: 191).Marković states that Ivan Lučić (Giovanni Lucio, Joannes Lucius) used that map (drawn by Buffalini) as a template for the map that was published in the third edition ofthe book De regno Dalmatiae et Croatiae ('On the Kingdom of Dalmatia and Croatia') in 1668 (Marković 1993: 182), while Slukan Altić has determined that it was a matter of "Gradić's map, taken over and modified" (Slukan Altić 2003: 132).Judging by the congruence of the geographical content, Lučić's 1668 map Illyricum hodiernum is unquestionably very similar to the 1663 manuscript map ofthe same area.Our cartometric analysis confirms that it is an almost facsimile depiction ofthe coastline ofthe northeast Adriatic coast, which differs from all older and contemporary representations of that coast on maps and charts selected as a research sample.
Ivan Lučić of Trogir's contribution to the making of the map Recent archival research by Gudelj resulted in her claim that "the map was made with the evident help of Gradić and the Trogir historian, Ivan Lučić" (Gudelj 2016: 191).In fact, at the time ofthe creation ofthe 1663 map of Illyricum, Ivan Lučić of Trogir, who succeeded Gradić as the leading man in the Fraternity ofSt Jerome also stayed in the College of St Jerome in Rome (Škrivanić 1968: 273).Dealing primarily with the map of Illyricum printed in 1668 and published in the book 'On the Kingdom of Dalmatia and Croatia', but also with the 1663 manuscript map of Illyricum, D. Mlinarić et al. ( 2012) state, relying on the correspondence of the geographical content, that it is Lučić's cartographic achievement.Lučić's authorship of the map, or at least his crucial co-authorial contribution to the shaping of its geographical content, is supported by his words written Slika 2. Karta "Današnjeg Ilirika" iz 1 669.objavljena u Blaeuovom Atlas Maior. in the work Memorie istoriche di Tragurio ora detto Traù ('Historical testimonies about Trogir'), published in 1673: "Whoever takes a closer look at various positions will see that, on maps printed thus far, there are many errors, not only in connection with the territory ofTrogir, but also with the entire Province.In order to correct this, I have made a new map oftoday's Illyricum, which consists of four provinces -Dalmatia, Croatia, Bosnia, and Slavonia -and, with various sketches and notes, I have corrected, to the best of my ability, the errors printed hitherto, encouraging whoever it pleases to look there at correctly drawn positions and to add those corrections that seem to him to be more accurate than what I have printed" (Lučić 1673(Lučić , translated 1979: 706: 706).Among the Croatian historians of cartography, Kozličić was the first to bring attention to this, pointing out that Lučić's maps have no real analogies in the history of mapping the eastern Adriatic (Kozličić 1995: 218, 220).
Lučić was aware ofthe fact that on that map ofIllyricum he had given a general depiction without sufficient detail, so in 1676, in a letter addressed to Danijel Difnik of Šibenik, he gave instructions that his brother (Franjo), who was preparing a comprehensive Historia della guerra di Dalmatia tra Venetiani e Turchi ('History of the Candian War in Dalmatia between the Venetians and the Turks'), be forwarded a proposal to supplement his work with a map ofDalmatia, more detailed than his, at least for the areas of Zadar, Šibenik, Trogir, Split and Omiš (Kečkemet 1986: 7-52).In the first edition of his work 'On the Kingdom of Dalmatia and Croatia', Lučić published five comprehensive and very generalized maps ofthe coastal part oftoday's Croatia.Not until the third edition of that book, published in 1668, was the map of 'Today's Illyricum' subsequently included, having been prepared for printing by the Dutch publisher and cartographer Joan Blaeu.Blaeu then published the same map in 1669 in the Atlas Maior /Geographia Blaviana (Figure 2).Blaeu's contribution was similar to that of Buffalini: Lučić (and other co-authors) did not deal with the technical aspect ofmapmaking, but he was crucial in defining its geographical content.
The publication ofthe printed map of'Today's Illyricum' enabled its dissemination throughout Europe.Although its communicative potential was great, it was soon replaced by maps depicting the same area, created by Giacomo Cantelli and Vincenzo Maria Coronelli.Coronelli's maps became templates that, with minor modifications, were prepared for printing by numerous European cartographers during the 18th century, so they became a model for shaping geographical perception, and for cartographic representation ofan area that is today an integral part ofthe Republic ofCroatia, in the era that preceded systematic geodetic surveying.On the other hand, the 1663 map ofIllyricum became one ofthe longest-lasting permanently-used manuscript maps; its original, framed and covered with glass like a painting, hangs to this day on the wall in a special room of the Pontifical Croatian College ofSt Jerome in Rome.
3 Geometric Features of the Coastal Part of the Map The coastal part of the 1663 map of Illyricum was metrically compared with the rendering ofthe coastline on the 1669 map of'Today's Illyricum' (published by the Dutch publisher and cartographer, Joan Blaeu) and on a selected sample of maps and charts made at the end of the 16th and during the 17th century (Table 1, Figure 3).Two from each group of maps and charts were produced approximately a century earlier (GAS_1570, HOM_1570, DAN_1580 and VOL_1593), and one from each group (JAN_1650 and COR_1688) was produced in approximately the same period as the map ofIllyricum (BUF_1663 and BLA_1669). 2 Maps from the sample were georeferenced using the Helmert transformation (Modenov and Parkhomenko, 1965: 77-93) on a sample of points that was standardized with regard to the coverage of the Adriatic Sea on them.For georeferencing maps showing the entire Adriatic Sea, 45 identical points were determined; on the DAN_1580 map, 39 (of the 45) points were determined; while the maps of Illyricum, which show only the eastern part ofthe Adriatic Sea, were georeferenced on the basis of20 (ofthe 45) identical points.The geometric accuracy ofthe maps was determined on the basis ofthe deviation (residual) oftheir identical points in relation to their corresponding reference points and is expressed using root mean squared error (RMSE) (Loomer 1987: 113, Bevington and Robinson 2003: 98-114, Jenny and Hurni 2011: 403-405, Nicolai 2014: 209-210, Penzkofer 2016: 27-28), in which the greater of the two values oferror, one per axis, is used as a measure ofaccuracy.In addition to georeferencing the maps, the coastline of the mainland stretching from the Bay 2 Errors in the geometry of georeferenced maps by axis (RMSE|dX| and RMSE|dY|) are originally calculated in their projected amounts, which depend on the geometry of the selected reference projection.In order to cancel the influence of the display deformations specific to the selected projection, the calculated locations of identical points must then be expressed as coordinates on the reference ellipsoid (LON, LAT) in degrees [°], and the errors of identical points converted into orthodromic distances between identical and reference points (d|LON| and d|LAT|) expressed in kilometres [km] (Table 2).
of Trieste to Durrës (corresponding to the coverage of the eastern part ofthe Adriatic Sea on the maps ofIllyricum) was vectorized on all the maps in the sample, in order to make it easier to determine whether certain types of cartographic templates were used, potentially, in creating the rendering of the east coast of the Adriatic Sea on the 1663 map of Illyricum, and whether improvements in the quality ofthe geographic content, in relation to earlier cartographic realizations, were achieved.The nautical charts in the selected sample (Table 1) showed the highest accuracy in comparison with the Mercator projection, in which deformations in representation ofdistance are least when it is set with a standard parallel of 0 =42.7°(MERC43), which is approximately the central parallel for the Adriatic Sea basin. 3Intervals of one degree of longitude (LON) and latitude (LAT) on the graticules on the three maps have a ratio (LON/LAT) of approximately 0.8°across the entire field of the map, which indicates that they were made in a normal equidistant cylindrical projection with standard parallel 0 =36°(EQD36), which corresponds to the central parallel ofthe Mediterranean Sea, and which was used by Marinus of Tyre for his maps of the ecumene (Snyder 1993: 6, Breggren andJones 2000: 33-34).
On the map of Illyricum printed in the atlas by Joan Blaeu (BLA_1669), this ratio is 0.73, which corresponds to a normal equidistant cylindrical projection with standard parallel 0 =42.8°(EQD43) 4 .The 1663 map of Illyricum (BUF_1663) does not contain the graticule, but the coastline rendering on it is visibly, even at a glance, very similar to the rendering on the 1669 map ofIllyricum.On this basis, it was assessed that both maps were made in the same projection, and map BUF_1663 was also georeferenced to a modern map given in the EQD43 projection.
In georeferencing the maps, it was determined that they show the highest accuracy (lowest RMSE values ofgeometric errors) precisely in comparison with these projections.Navigational charts show a larger mean latitudinal error (RMSE d|LAT|) versus average mean longitudinal error (RMSE d|LON|), while for all the maps in the sample (including the 1663 and 1669 maps of Illyricum), the average errors oflongitude are greater (Table 2).Average RMSE d|LON| errors of the two maps of Illyricum are lower than the errors on the other maps by about 3 km, but it is not possible to compare the two sets of maps, since fewer than half the number of identical points were used for georeferencing the maps ofIllyricum. 5he rounded average scale ofthe 1663 map ofIllyricum, according to distance measurements on the map and in GIS software (QGIS), is 1:450,000.Measurements of distance were made on five segments -Cape Permantura -Zadar, Zadar -Cape Ploča, Cape Ploča -Cape Lovište (Pelješac), and Cape Lovište -mouth ofthe River Drim -and compared with their lengths on a modern map in the EQD43 projection at a scale of1:1 (deformations caused by map projection were taken into account).The standard deviation (SD) amounts to 36,581, i.e. about 8%, with the largest deviation from the average recorded for the southern part (measurement of Cape Lovište -mouth ofthe River Drim), without which the SD would amount to 27,201, i.e. about 6%.The linear scale on the map is indicated in Italian land miles (Scala di Miglia treara Italiane).It represents a distance of30 miles and has a total length of 109 mm, and is divided into three larger intervals of 10 miles each (36 mm in length per interval), while one larger interval is further divided into 10 smaller ones (3.6 mm in length), each of which represents one mile.On a georeferenced map, those 30 map miles correspond to a distance of 47.4 km, which would mean that one mile equals 1.58 km -a value that roughly corresponds to one Tuscan mile of1,654 m (Treese 2018: 145).The scale of Buffalini's map derived exclusively on the basis ofthe linear scale is 1:434,862.
The representation ofthe area ofIllyricum on the map is rotated by (−35°), with respect to the direction of the sign for north, but during georeferencing of the map it was found that the rotation of the display (Ɵ) is (−27°), which would mean that the north direction on the map has a deviation of(−8°) in relation to the rotation resulting 3 The distinct geometric similarity of the rendering of the Adriatic Sea on portolan maps (regardless of the year of their creation) to its rendering on a map in the Mercator projection is demonstrated in detail by Marelić (2022: 16-17). 4On a map in normal equidistant cylindrical projection, the map scale is true along all meridians and along standard parallels.When the shape of the Earth is approximated to the shape of a sphere (as the Earth was considered for most of the history of cartography), the length of a copy of the arc of half of the standard parallel ( 0 ) on such a map in relation to the length of a copy of the arc of a meridian (half a great circle) is determined by the expression cos 0 .
Tablica 1 .Uzorak geografskih i pomorskih karata.from the conformal transformation ofthe map in the GIS software.However, on the basis of these values, it is not possible to determine with what accuracy the author performed the rotation of the display, because: a) georeferencing was performed on a sample of only 20 coastal points, and the display ofthe coast makes up a relatively small part ofthe total display ofarea on that map, and b) the accuracy ofthe coastal part ofthe map shows positional errors, which probably also exist on the rest of the display, which has not been metrically analysed.
The appearance ofthe coastline on the 1663 map ofIllyricum on most ofthe eastern coast ofthe Adriatic Sea is extremely similar to its appearance on the 1668 map ofIllyricum (like on Blaeu's 1669 edition ofthe same map).Visible differences exist only in the rendering ofthe extreme southeast part of the coast, but this difference is caused mostly by a change in the appearance ofthe peninsula of Pelješac, because of which, on the 1668 (1669) map of Illyricum, there was a relative transposition ofthe coast south ofit in a southerly direction.Ifthe transposition ofthat segment of the coast is ignored, the far southeast part of the coast is, with the exception of the rendering of the Drim delta, very similarly drawn on both maps.
The maps ofIllyricum are most accurate in comparison to the EQD43 projection, while the nautical charts are most accurate in comparison to the MERC43 projection, and the geographic maps are most accurate in comparison to the EQD36 projection.The mainland coastline of the eastern part of the Adriatic Sea was vectorized on all eight maps/charts in the projection relative to which they show the highest geometric accuracy, which is why (for the purpose of comparing the appearance of the coastline on these maps/charts with its appearance on the maps of Illyricum in the same coordinate system) subsequent reprojection was performed of these vector data into the EQD43 system (Figure 4, Figure 5).The rendering ofthe coast ofIstria on the 1663 and 1669 maps ofIllyricum is less accurate than its rendering on the maps/charts they were compared to, especially in relation to the rendering ofthe coast of Istria on the nautical charts.On the other hand, the rendering ofthe area below Velebit, especially the part between Senj and Karlobag, is shown more reliably on the 1663 and 1669 maps of Illyricum than on the selected examples of maps and charts.The area of northern Dalmatia is most reliably drawn on the three geographic maps (least reliably on the nautical charts).The perception of that part ofthe coast is very realistic, but it shows deviations in the approximated axis of extension of the coast, while the whole ofsouthern and central Dalmatia is shown similarly to the geographic maps, with the exception of Danti's map ofItalia nova, where there are large deviations in this respect.In the preparation ofthe research, we assumed that that particular map could have had an important influence on the rendering of the coastline on the 1663 map of Illyricum.That map is, in fact, one of the maps in the Gallery of Geographic Maps in the Vatican Palace created in 1581 by cartographer Ignazio Danti.In 1631, Pope Urban VIII (Barberini) charged the Vatican librarian and Table 2 The geometric accuracy of coastline renderings on Illyricum maps (VAT_1 663, BLE_1 669) in comparison with coastline renderings on selected older and contemporary maps and charts on which the Adriatic Sea is represented.Tablica 2. Geometrijska točnost prikaza obale na kartama Ilirika (VAT_1 663, BLE_1 669) u usporedbi s prikazom obale na odabranim starijim i suvremenim geografskim i pomorskim kartama na kojima je prikazano Jadransko more.Veća od dvije RMSE vrijednosti po osima, koja predstavlja metriku za iskazivanje točnosti karte je podebljana.
Karte Ilirika najtočnije su u odnosu na projekciju EQD43, dok su pomorske karte najtočnije u odnosu na projekciju MERC43, a geografske karte u odnosu na projekciju EQD36.Obalna crta kopna istočnog dijela Jadranskog mora vektorizirana je na svih osam karata u projekciji u odnosu na koju pokazuju najveću geometrijsku točnost, zbog čega je (u svrhu usporedbe izgleda obalne crte na tim kartama s njezinim izgledom na kartama Ilirika u istom koordinatnom sustavu) izvedeno naknadno reprojiciranje tih vektorskih podataka u sustav EQD43 (slika 4, slika 5).Prikaz obale Istre je na kartama Ilirika iz 1663.i 1669.manje točan u odnosu na njegov prikaz na uspoređenim kartama, poglavito u odnosu na prikaz obale Istre na pomorskim kartama.S druge strane, prikaz podvelebitskog prostora, poglavito dijela između Senja i Karlobaga, je na kartama Ilirika iz 1663.i 1669.prikazan vjerodostojnije u odnosu na odabrane primjere geografskih i pomorskih karata.Prostor sjeverne Dalmacije je najvjerodostojnije prikazan na trima geografskim kartama (najmanje vjerodostojno na pomorskim kartama).Percepcija tog dijela obale vrlo je realistična no pokazuje odstupanja u aproksimiranoj osi pružanja obale, dok je čitava južna i srednja Dalmacija prikazana slično kao i na geografskim kartama, izuzev Dantijeve karte Italia nova kod koje u tom pogledu postoje velika odstupanja.U cartographic erudite, Lukas Holstein, with updating the geographic content of the maps, which Holstein did with regard to the Italia nova map (Fiorani 1996, 128), but the exact extent ofhis interventions on that map and a number ofothers is not known.(He did not attend to all the maps in the Gallery.)Given that Stjepan Gradić was appointed advisor to the Sacred Congregation of the Index in 1658, and curator ofthe Vatican Library in 1661 (Martinović 1983: 14), he certainly had access to the Gallery, where he could consult Danti's maps (with Holstein's additions).Access to the Gallery was also possible for Buffalini, thanks to good connections with the Barberini family (cf.Gudelj 2016: 193).However, cartometric analysis did not confirm accordance ofthe content ofthe Italia nova map with the 1663 map of Illyricum.Nor is the rendering ofthe coastline on the 1663 and 1669 maps ofIllyricum similar to the rendering ofthe Holstein u pogledu karte Italia nova i obavio (Fiorani, 1996: 128), ali nije poznat točan sadržaj njegovih intervencija na toj i još nekolicini karata (nije intervenirao u sve karte iz Galerije).S obzirom na to da je Stjepan Gradić 1658.godine bio imenovan savjetnikom Svete Kongregacije indeksa, a 1661.godine kustosom Vatikanske knjižnice (Martinović 1983: 14), zasigurno je imao pristup Galeriji u kojoj je mogao konzultirati Dantijeve karte same area on the nautical charts of the sample, which indicates that Lučić did not use them as graphic templates for creating the maps ofIllyricum.However, some traces clearly point to some of the cartographic sources used.Among others, there was most likely the original 1589 map of Croatia, Dalmatia and Slavonia by Mercator, numerous versions ofwhich were printed, and thus widely available even in the 17th century.Mercator's traces were not noticeable in the rendering ofthe coastline as one ofthe key geographic contents that greatly define the appearance of the depicted region (Figure 6), was recorded in his mistake of showing Zagreb twice: Agram at the proper location, and Zagrabije near the confluence ofthe Kupa and Sava, near Sisak.It is odd that Lučić, or any of his associates, did not notice and then correct this mistake.Evidently, they, like many other cartographers of the time, were strongly influenced by authorities in the field of geography and cartography on the one hand; and, on the other, they uncritically compiled various data sources without checking whether inconsistent mosaics of content thus arose.Therefore, his contemporary Stjepan Glavač was correct in writing, in the dedicatory cartouche ofhis map ofCroatia (in a narrower sense) printed in 1673: "When I think that all the neighbouring provinces have maps made (as I was partly taught by experience of travel, and partly by reliable connections with learned people from those areas), the description of our Homeland alone is composed so superficially that it hardly contains any true notion.For much ofit lies in the wrong place, much that is worthy ofmention has been omitted, and much has been somewhat ludicrously crammed in; to remain silent about much else, it is enough to see how it has been concluded that Agram and Zagreb are two cities, two miles apart, which is not true at all, the only difference being that one name is German and the other Latin" (translated from Marković 1998, 381-382).At the same time, it should be pointed out that the spatial scope of "our Homeland", i.e.Croatia as perceived and depicted by Glavač accords with what was called, in early modern vocabulary, the remains ofthe remains ofthe once great and glorious Kingdom of Croatia (reliquiae reliquiarum olim magni et inclyti regni Croatiae), and not the entire area shown on the 1663 map ofIllyricum.

Conclusion
Through research on the original map of Illyricum, which is kept in the Pontifical Croatian College of St Jerome in Rome, Ivan Lučić was confirmed as one of the key (co)authors of the map.Lučić correctly demurs, claiming only that his map was an attempt to correct many "mistakes" in the depiction ofthe same area, but he encouraged "whoever it pleases to look there at correctly drawn positions and to add those corrections that seem to him to be more accurate than what I have printed".Despite the progress in the presentation of certain geographical elements, Lučić (as well as other co-authors) still did not know the geographical features of the area depicted well enough, for he certainly did not travel throughout it, let alone make topographical observations or organize and carry out metrologically demanding surveying?procedures.The co-authors ofthe map ofthe four Croatian spatial units with the politico-legal categories of kingdoms -Dalmatia, Croatia, Slavonia and Bosnia -thus remained within the framework of a frequently-applied method in shaping the content of the small-scale maps that were made in the second halfofthe 17th century: on the basis of a compilation of existing maps, those elements of the geographic content that the co-authors knew well, either empirically or on the basis of available archival documentation, were supplemented or altered in places.With regard to their scientific focus, although very broad, Lučić and other participants in that cartographic endeavour could not make any improvements from a geodetic point of view, but empirically they still rendered the coastline ofthe northeast part ofthe Adriatic significantly better than had been shown on maps and charts until that time.It is possible to establish that the most important co-authorial contribution to the map of Illyricum drawn by Buffalini was that of Lučić, and following Marković and Gudelj, the contributions of Gradić and other members of the Croatian community ofSt Jerome in Rome cannot be ignored, either.In view of Lučić's contributions to the creation of the maps of Illyricum, it is not justifiable to attribute the 1663 map exclusively to Buffalini, or the 1669 map (and later editions) exclusively to Blaeu.When attributing these maps, it is most appropriate to follow the words of Lučić from his work 'Historical testimonies about Trogir' -which are similar, in key parts, to the text in the cartouche of the 1663 map -i.e. to call that map Lučić's map ofIllyricum, ofwhich the prototype was drawn by Buffalini in 1663, and the printed version was produced by Blaeu in 1669.

Note
This paper is the result ofresearch carried out within scientific project IP-2020-02-5339, Early Modern Nautical Charts ofthe Adriatic Sea: Source ofKnowledge, Means ofNavigation and Medium ofCommunication, funded by the Croatian Science Foundation.

Table 1
Research sample of maps and charts.
The greater oftwo axial map/chart RMSE values, which represents its accuracy metric, is put in bold.