A good example of how archaeological finds of the late Middle Ages and early Modern Age supplement archive sources are stove-tiles found in the course of archaeological excavations over a number of years of medieval fortified castles of Ružica-burg and Ilok. Besides being a visual art and artistic value they are an excellent example for the research of family, political and business connections and economic power of the Dukes of Ilok, who as owners and builders of these two most valuable mediaeval complex in Eastern Croatia played crucial role in Hungarian-Croatian Kingdom from the second half of the 14th century until Turkish seizure. Nikola of Ilok (died in 1477) and his son Lovro (died in 1524) were the main bearers of these family’s powers. Their sepulchral slabs in the church of St. John Capistran in Ilok were starting points of my research and reflection on heraldic heritage of this family and indistinctness referring to particular coats of arms and their origin. While processing huge amounts of stove-tiles found at Ružica-burg, fragments with images of different coats of arms drew a particular attention. Although they seemed at first to be imported stove-tiles i.e. the moulds so that the coats of arms had more of aesthetic purpose the detailed analysis resulted in a smaller number of coats of arms (fig. 3, 4, 5, 6, 7) of this type. The other group of coats of arms comprises state i.e. royal coats of arms such as Hungarian, Austrian, Bohemian or Portuguese (fig. 8, 10, 11, 12, 13, 14, 15, 16). The coat of arms of the Pecs bishop of Sigismund Ernuszt has been found almost intact. The small coat of arms of Portugal is ‘‘odd’’ only at first impression. However, keeping in mind the conflict between Nikola of Ilok and the King Matthias Corvinus (1458-1490) and Nikola’s inclination and connections with Austrian Emperor Friedrich III of Habsburg, Roman-German Emperor 1452-1492, whose wife was the Portuguese princess Eleonor (died in 1467) this coat of arms is a confirmation that stove-tiles motifs on show-piece stoves at special court premises such as festivity halls, dining halls, chapels, yards etc. had not been selected by chance (fig. 16). The same applies to the fragment of the coat of arms of Kyburg, an estate in the vicinity of Habsburg (now Switzerland), which was inherited by marriage of Rudolph of Habsburg (1218-1291) (fig. 17). Similar features are carried by the fragment of unglazed terracotta with black bird image presumably raven- the family symbol of the King Matthias Corvinus (fig. 18). The third group of coats of arms gives us the most information and refers to those coats of arms that reached the families through family bonds. These are the fragments of several coats of arms of the Gorjanski family (fig. 19, 20) since Lovro’s sister Euphrosyne was married to Job, who was the last Gorjanski (died 1481). Lovro’s sister Hyeronima was married to Leonhard, the count of Gorica, the part of whose coat of arms was found on Ružica (fig. 21). The sepulchral slab of Leonhard, the count of Gorica and Tyrol in Lienz contains a fragment of the Carinthia coat of arms (fig. 22) as well; a fragment of the Counts of Celje (fig. 23) was also found. The coat of arms fragments that had obviously been a part of a larger stove tile in the crest of a luxurious tile stove are of special interest. The rest of the lower part, glazed in green, indicates that the coat of arms was slightly slanted to the right, leaning to the Gothic balustrade of the large gable stove tile from the stove crest. It was probably a part of a pair together with another coat of arms slanted to the left, with an axe image. The combination of the two motifs is depicted on the sepulchral slab of Lovro of Ilok. The reconstructin (drawing) of this coat of arms established that it contains the motive of a four posted bower, the roof of which is made of four layers of straw bound to a knot on the top (fig. 25, 33). The constant issue in the course of research of the stove tiles and finds from Ružica was connected to non-existence of a single item that would bear at least one of the coats of arms of the Dukes of Ilok known in literature, i.e. that are on the sepulchral slabs or seals (fig. 1, 2, 28, 35). Almost the same statement could be applied to the stove tiles found during archaeological research in Ilok. The analyses of the existing coats of arms on sepulchral slab of Nikola of Ilok and his son Lovro have shown that preserved coats of arms on Nikolas’ a slab are known and they depict coats of arms of the Bosnian Kingdom with three crowns (Nikola’s title was the King of Bosnia), i.e. the old family coat of arms with the image of two laid beams. Subsequent intervention and attempts to insert some randomly selected and poorly made coats of arms are completely unfounded. The stone fragment with finely carved coat of arms on a similar red stone (without an inventory number) that is in the holdings of the Museum of the Town of Ilok (fig.29) is not the part of Nikola’s sepulchral slab, either. The Renaissance image of a shell which comprises the mentioned coat of arms is similar to that on which two putti hold the shell with an empty shield (coat of arms is chiselled off) and with the subsequently chiselled year of 1797. The fragment with the coat of arms of the Dukes of Ilok must have been in the same position between two putti. There is another fragment with one putto in the Museum of the Town of Ilok; however the breach line indicates that the fragment of the coat of arms of the Dukes of Ilok did not make a whole to fit. The rests of iron clamps on both fragments indicate that this was a frieze (cornice with coat of arms), i.e. the coats of arms of the Dukes of Ilok, one of which was a fragment with a quartered coat of arms and a bower in its third quarter. These could be also coats of arms of the families with whom the Dukes of Ilok were in family ties, as well as the state i.e. royal coat of arms. Sepulchral slab of Lovro of Ilok has been preserved almost intact (a part of the inscription in its left corner is missing) and it comprises four coats of arms preserved in its entirety. Besides the first three known coats of arms (the coat of arms of Bosnia, of the Dukes of Ilok and Lovro’s wife Katarina Pongracz de Dengelog), the fourth coat of arms of an unknown origin comprises the motif on the right side of the shield for which it was not clear what it depicted, which is the key to its origin. The vagueness of form and function of this quite effaced and indistinct object rendered the finding out of its significance and function impossible. It was only by notification of stove tile from Ružica and subsequent analysis that I managed to establish that the fourth coat of arms on Lovro’s slab comprises the same four-posted bower with a straw roof bound in a knot on its top that is also depicted on the coat of arms i.e. the stove tile that formed the tile stove crest at Ružica burg (fig. 25). The mentioned fragment of the red stone slab in the Museum of Ilok bearing a nicely dressed smaller coat of arms should be noted in this context. On this quartered coat of arms in the upper left corner there is an old coat of arms of the Dukes of Ilok with two laid beams (2nd quarter. In the upper right corner (1st quarter) there is a Hungarian cross and in the lower left corner (4th quarter ) an axe turned to the left, which is the same motif as on the fourth coat of arms on Lovro’s slab. The third quarter is of the greatest significance obviously containing the motif of a bower with a four layered roof, that is here round-shaped (semi-cicular) for the «restricted space» on the 3rd quarter (the shield is slightly bent). It is particularly interesting that four posts of the bower are depicted as a pruned tree trunk. Finally, we should note an importat find of the completely preserved niche-shaped tile that was excavated in the course of archaeological excavations within the mediaeval palace of the Dukes of Ilok in Ilok over a number of years. Within the niche of the green glazed and partially reconstructed stove tile there is an image of quartered coat of arms depicting a common cross in its first quarter. In the 2nd quarter there is an old coat of arms of the Dukes of Ilok with two laid beams whereas the 3rd quarter depicts two pruned tree trunks with a round tree top and probably an image of a snake raised along the left tree. The 4th quarter was destroyed and reconstructed as a flat surface and it could have depicted an axe. Thus, it should be concluded that we deal with an image of the same coat of arms from the fragment from the Museum of Ilok with modifications that first of all reflect an unskilful stove maker, i.e. the mould maker. It is questionable why the tile from Ružica that comprises a coat of arms with a bower lacks an axe unlike other images, however the possibility should be reconsidered that besides this coat of arms slanted to the right within the big crest of the tile there was also a coat of arms with an axe slanted to the left. The rests of the olive-green glaze (for reinforcing the construction), i.e. the breach in the upper right corner on the coat of arms with a bower where it was connected to the other coat of arms, speak for the fact. The coats of arms of the Dukes of Ilok and their variations in professional literature were reproduced i.e. drawn based on preserved seals on charters and images on stone monuments. The oldest coat of arms in whose shield there are two laid beams, a helmet with a crown out of which a crowned winged virgin appears, could be found earlier on seals of Nikola Kont in 1359 and 1364. Such a seal can be found both on the sepulchral slab of Nikola of Ilok and his seals. The second coat of arms can be found on seals and on sepulchral slab of Lovro of Ilok. This quartered coat of arms from the sepulchral slab of the Dukes of Ilok was probably used only by Lovro of Ilok. This counts for the third coat of arms that was no