A key phenomenon of today's global economy can be observed in the concentration of capital in financial centers and the extent of financial interconnections between international financial centers. Financial centers serve as a gateway for the circulation of capital. The question arises as to how the international financial centers are interconnected. When we look at the real economy, it becomes clear that this question is difficult to answer. Because in the real economy, individual countries are viewed as point markets. Spatial aspects are shown at most as transport costs between countries. The spatial structure of the countries involved and the complex structures of the financial center networks are not depicted. Individual aspects are considered in theory and empirically, but there is no comprehensive theory to explain the existing interconnections between economic centers, especially financial centers. With regard to the empirical data on this area, a different picture emerges. There are numerous statistics and analyzes available about financial interconnectedness. The problem with this is that, especially when it comes to public statistics, in most cases the focus is on data at the country level rather than at the financial center level, which only affects the financial centers to a limited extent. In addition, bilateral capital flows between financial centers and regions are often not reflected in these data. On the other hand, there are empirical studies by research institutes and rating agencies that are explicitly aimed at financial centers and use a series of criteria to try to develop an index for assessing the importance of the financial centers under consideration. Despite a comprehensive analysis, the relationships between the financial centers and their changes are hardly discussed here. The various approaches therefore only have limited informative value. In order to close this gap, this work aims to systematically research the interconnections between international financial centers. At the theoretical level, the aim is to form a sound basis about the economic centers, especially the financial centers. At the empirical level, the focus is on developing a methodology using network analysis that is able to systematically examine the interconnections between international financial centers. The analysis is carried out at different levels, these are: at the financial center level, at the country level and at the regional level. The study of the financial center level is carried out based on the location selection of the banks' subsidiaries. At the country level, the value analyzes of receivables and liabilities, imports and exports as well as (Foreign direct investments) FDI are used. The results from the country level are aggregated at the regional level. Network analysis is illuminated by various aspects. At the financial center level, among other things, the cliques of the financial centers are formed and the degree of connection within the network is worked out. At the country level, the country cliques are highlighted for each aspect in two periods and the changes are made clear. The "outdegree" and "indegree", which reflect the directed financial flows depending on the context, are developed. Finally, the results of the study from all aspects and levels are brought together, in order to consider the characteristics of financial interlocking at the overall level. The original question about the structure of financial interlocking is thus answered. The results of this methodology are exemplary. Rather, this research approach offers a generally usable and systematic research methodology that can be transferred to other countries and other time periods.