The research of the dissertation has covered thirteen parish and thirty-four filial chapels recorded in seventeenth-century canonical visitations of the Archdeaconry of Varaždin, one of fourteen archdeaconries of Zagreb diocese. Although certain documents from the fourteenth and fifteenth century do mention religious buildings in that area, the posttridentine canonical visitations are the first known written sources to offer comprehensive and rather detailed information on their architectural shapes, interior furnishings and liturgical objects. The visitation records dating from 1638 to 1698 (kept in Zagreb Archdiocese Archives) are the oldest sources of their kind for the Archdeaconry of Varaždin. Their importance for art-historical research lies in the fact that it was precisely during the seventeenth century that churches in that area had been adapted to suit the demands of the Roman Rite, officially prescribed by the decrees of the Council of Trent (1544–1563). The Council, one of the largest ecumenical councils in the history, met for twenty years to invigorate the renewal of Roman Catholic Church after the spread of Protestantism. Being one of the active participants of the Council sessions, Bishop Juraj II Drašković of Zagreb had also a crucial role for the implementation of its deliberations in his diocese. Canonical visitations were one of the major topics on Council’s agenda. Although bishops had been periodically visiting churches under their jurisdiction throughout the medieval times, in pre-tridentine period the duty was often neglected and lost much of its significance. The Council re-established the responsibility of prelates therein, thus reaffirming visitations as a principal means of communication between a pope, bishops and lower clergy. Their main purpose was to monitor and correct anything concerning the cure of the souls. Amongst other, visitation reports included systematically gathered data on buildings and their interiors that were relevant for the Divine service. In seventeenth century, canonical visitations of the Archdeaconry of Varaždin were performed by archdeacons authorised by bishop. They were usually carried out in the first part of the year and would last approximately a month during which the visitators would examine 219 the conditions of all thirteen parish churches and thirty filial chapels. There were two basic types of visitations, resulting in two types of visitations reports. Fundamental visitations (visitationes fundamentales) that were performed every five years produced comprehensive accounts on visited parishes and their churches, whereas those made in course of the 'regular', yearly visitations deal only with the changes that have happened since the last visit. The records of four fundamental and twenty-four 'regular' visitations of the Archdeaconry of Varaždin, are preserved until the present day. They are written in Latin and most of them are not published. The structure of the records, i.e. the sequence of chapters and their contents, strictly follows the directions given in Charles Borromeo's book Instructiones fabricae et suppellectilis ecclesiasticae. Being unquestionably the most important reference work of its time for the subject-matter, it was also most influential 'handbook' for the postcouncil renewal of church buildings and their interiors. The comprehensive study of the archival material and field research of preserved monuments has been conducted for the dissertation. All data concerning the architecture, interior furnishings, and inventory of the parish and filial churches (e.g. altars, pulpits, liturgical fabrics and vessels, books, etc.) were excerpted, systemized and compared to the actual condition of each building. As a matter of fact, up to the present day only six parish churches and fifteen chapels have retained their seventeenth-century appearances. Furthermore, in order to interpret the different phenomena, all relevant scientific and professional literature has been studied, particularly the art history works, but also those regarding social and ecclesiastical history of the period within the wider geographical area. The research has confirmed that, in the seventeenth century, the majority of parish churches and filial chapels in Varaždin Archdeaconry belonged to a traditional (i.e. the medieval) type which combined single-nave timber-roofed longitudinal body with narrower and lower vaulted polygonal sanctuary. In course of the examined period all of them have been gradually altered, renewed and embellished according to Council decrees. In view of functionality, their architectural shapes were enhanced using the prescribed materials of better quality. Wooden parts of the church complexes (e.g. belfries, auxiliary structures) were replaced by masonry structures and most parish churches had their sacristies added. Interiors were abundantly furnished with new altars and pulpits; new liturgical fabrics and vessels were provided. 220 The concluding chapters address issues which reveal most significant differences with regard to the previous (i.e. pre-tridentine) period. Particular attention is given to the profound changes in the 'iconography' of church interiors as well as the overall dynamics of the implementation of Tridentine regulations. As regarding the frequency and the amount of investment, the evident fluctuations in the numbers of liturgical vessels confirm the practice according to which major building campaigns were preceded by converting the value of precious metal objects into the money. Along with the analysis of the positions of churches within the seventeenth-century network of roads and settlements, the role played by feudal lords acting as church patrons deserved to be emphasized. However, most of the examined buildings underwent significant reconstructions during the following (eighteenth and nineteenth) centuries. That is precisely the reason why the records of canonical visitations proved to be of more importance for the study of the past architecture than expected.