At the time when the prosperity of the Dubrovnik Republic was at its peak, the historical core was the only administrative, political, social, commercial and residential centre. Through the millennial history of Dubrovnik, the size of the population of both city and republic depended on social and political circumstances. Years of political calm and prosperity led to demographic growth, while times marked by wars, disturbances, epidemics and natural disasters brought about a decline in the population. But at the turn of the 20th and 21st centuries, Dubrovnik was faced with totally new challenges requiring the urgent revitalisation of and the perpetuation of normal life in the historic core, which is threatened with the wholesale depopulation. The depopulation of the old city centre acquired additional impetus in the last five decades of the 20th century, as manifested by the ongoing emigration of the inhabitants and the great decline in natural population growth. There are several reasons for this. As a result of modernisation and changes in the manner of life, many found the centre unattractive for living in, while as a result of the development of tourism in the Dubrovnik region it acquired a new attraction as a tourist centre in which today tourism and hospitality activities prevail, without even minimum contents for the local population. In addition, many of the residents have sold their dwellings or converted them into apartments for letting to the many visitors to the city. These economic and social processes have been reflected in population trends, bringing about huge changes in population structure, and leading to emigration and a drastic rise of the elderly population. Previous research into the population of the historical core of Dubrovnik during the period of the depopulation of the last few decades has on the whole been founded on official statistics. However, there are strong indications that official figures at this micro-location deviate considerably from the real state of affairs. The reasons for this divergence are not unambiguous. A large number of local migrations (mainly concerned here are cases in which people move out) are not properly administratively recorded. Many people are still registered at their old addresses, whether out of inertia or from the desire to retain some right. Until recently the existence of areas of special state concern in the immediate vicinity (Mokošica, Župa dubrovačka and Konavle) inclined some inhabitants of the city centre to be registered for administrative purposes in these areas. This kind of chaos, the ignorance of the real facts, necessarily implies mistakes being made in conclusions drawn at the academic level as well as errors in the adoption of population measures. Since the process of depopulation within the historical core of Dubrovnik has not been fundamentally investigated, even though it was observed long since, within the context of the “History of Population” doctoral course conducted jointly by Zagreb and Dubrovnik universities in collaboration with the Croatian Academy of Sciences and Arts Institute for Historical Sciences in Dubrovnik, and supported by the City of Dubrovnik, a project was initiated that deals precisely with this problem area - the movement of the population out of the historical core of Dubrovnik. A four-part questionnaire was administered, the aim of it being to determine a demographic picture of the inhabitants. The objective was to find out how many persons really lived within the walls, particularly since it was noted that for various reasons official statistics overestimated the size of the population, and to determine the familial, age, gender and economic and educational structures of the population. The questionnaire was administered to inhabitants of the historical core of Dubrovnik from March to June 2011, the critical moment of the census being taken as March 31, 2011. Starting off from the premise that for a truthful analysis of population trends it is crucial to know the exact values of individual demographic indicators, and that only on the basis of such data is it possible to draw valid scientific conclusions, and thus to implement at the political level effective population measures, the goal of the research described in this dissertation was to attempt via various methods to obtain a deep insight into the demographic characteristics of the city’s population, its age, gender and family structure, understand its life in contemporary conditions and as a part of the whole of the City of Dubrovnik. The work draws not only on the results of the 2011 questionnaire but on various other sources: archival and statistical, as well as secondary sources such as those produced by the city government and the Church for various purposes, which were also a foundation for the elaboration of an initial database underpinning the approach to polling the population. Mainly fieldwork has been involved in the research, and the results are backed with numerous tabular and graphic depictions. A comparative method, of course, is indispensable particularly in those parts of the dissertation that depict population trends through history, define the causes of depopulation and endeavour to fit the old core of Dubrovnik into the wider context of population trends of similar historical nuclei in other parts of Croatia. Demographic trends in the Dubrovnik historic centre are compared with those in the cores of Split, Zadar and Šibenik, for they too are faced today with accelerating depopulation. The dissertation itself is divided into five chapters according to theme. The introductory chapter erects the hypothesis of the study, sets forth the objectives and the research methodology, as well as a survey of previous knowledge and a review of censuses in the Dubrovnik area. Chapter Two describes the development of the population of the historical core of Dubrovnik through history, according to the most recent estimations, accessible references and censuses. A short analysis of the population from the very beginnings of the city, in the age of the Dubrovnik Republic, and after its fall, is accompanied by an analysis of the total trends in the population of the city within the walls according to the French (1807) and Austrian (1817 and 1830) censuses, and in the period of modern statistics (from 1857 to 2011). A comparison is given of the population trends of the settlement of Dubrovnik and its old core, and their ratio in terms of figures, in order to be able to determine any similarities or differences. Since detailed data are available only from 1981, the emphasis is placed on the analysis of the main demographic indicators in population trends in the historic core of Dubrovnik according to the separately processed figures of the censuses of 1981, 1991, 2001 and 2011 obtained from the Croatian Bureau of Statistics. The Third and main part of this dissertation consists of an analysis of the questionnaire administered to the inhabitants living within the city walls in 2011, a description of the procedure, the selection of the basic set, a definition of the size of sample, the formulation of the questionnaire and at the end an analysis of the data gathered. This part of the dissertation covers an analysis of demographic indicators obtained both via the questionnaire and via estimations on the basis of a critical verification of official statistical data (number of inhabitants, various structures of the population, such as familial, social and economic). Chapter Four analyses in detail the process of depopulation within the historical centre and the influence of social and economic factors on population trends in the 20th and at the beginning of the 21st century, in order to determine the causes and consequences of the process. Particular emphasis is placed on tourism and cruiser-tourism and their influence on the transformation of the old city centre from a place of permanent residence to a place for temporary sojourn, in other words, for tourist lets. When the figures for the numbers of visitors to the Dubrovnik area and for the trend in the total population of the historical centre of Dubrovnik during the 20th century are juxtaposed, it is shown that the rise in the number of visitors from the 1960s correlates with the rapid decline in the size of the population of the city bounded by the walls. Unfortunately, in the academic literature to date, there has been no comprehensive handling of the influence of tourism and cruiser-tourism on population trends in the historic core of Dubrovnik. Hence the accessible sources and scholarly dissertations and studies (which have only partially or incidentally mentioned the influence of tourism development on trends in the size of the population of the old city centre) are used to put forward all the processes of social and economic transformation that have unfolded in the old nucleus under the impact of mass tourism and cruiser tourism. Ultimately these have made it impossible to maintain any coexistence of tourists and city population and have led to depopulation. Data gathered from several institutions, such as the Tourist Board of the City of Dubrovnik, the Marin Getaldić Elementary School, the parishes of the city, the Dubrovnik city authority, and the office of the state administration in the Dubrovnik-Neretva County, also indicate that tourism development in the Dubrovnik area in the last half a century has been influential in the reduction of the number of inhabitants of the old city centre. The Dubrovnik historic centre is not a lone phenomenon. The problem of the dying-out of old historic centres as a result of the processes of modernisation can be seen in many Croatian historic cities, such as Split, Zadar and Šibenik. One of the aims of this dissertation was to observe the similarities and differences in the population trends of similar city nuclei in Dalmatia. Accordingly the Fifth part of the dissertation undertakes a comparative analysis. The results obtained from Dubrovnik are compared with those related to population trends in the historical cores of Split, Zadar and Šibenik. These Dalmatian cities have well-preserved city centres, but are also faced with the emigration of the population under the impact of mass tourism.