Subnational regionalism is understood as ideology and movement of the subnational community, aimed at the political constituting of the subnational administrative-territorial unit, its acquisition of political subjectivity, its inclusion in the political process.

Regionalism should be considered as a complex phenomenon that differs (and has to be classified) in several dimensions: a) constituent ground of regional identity (historical, geographical, economic, ethnocultural, etc.); b) political purposes (reactive - proactive); c) political mobilization strategies (moderate - radical); d) place in the party-ideological spectrum from the view of a political position regarding national problems (left-right scale); e) the degree of internal consolidation of regionalist movement (consolidated - fragmented); f) the intensity of regional identity in the context of an identification matrix, etc.

Multi-level politics is assumed as a new mode of political interactions which are characterized by pluralistic, dispersed activity of a great number of actors, which interact with each other at different and interrelated levels of government.

C. Alcantara, J. Broschek and J. Nelles distinguish the two basic configurations of multi-level politics: 1) “intergovernmental relations” (IGR), which include regional and local governments in policy process; 2) “multi-level governance” (MLG), which assumes that non-governmental actors of different levels are involved in policy process. The other and rather dynamic dimension of the configuration of multi-level political interactions was developed by G. Marks and L. Hooghe. Here the Type I is characterized by fairly institutionalized and unified (from the view of the different administrative units) in a single logic of actors’ engagement in policy process. Unlike, the Type II is characterized by flexible and diversified practices of inclusion of actors. It means that various sets of actors and rules of their interactions appear on different arenas and in the relation with different territorial units.

The project was aimed at determining the scope and mechanisms of the influence of subnational regionalism (among other factors) on the configuration and dynamics of multilevel politics. Solving the problem of developing a theoretical and methodological basis for the project, the research team, first of all, focuses on the operationalization of the research model. Conceptual analysis of regionalism made it possible to theoretically link some different connotations. Regionalism as an intense regional identity is a sociocultural foundation and a condition for the emergence of regionalism as a movement, although it does not always develop into it. The conventional definition of regionalism as a movement, which demands territorial autonomy of a region in a unitary state, has been clarified, since regionalist demands don’t limited by getting autonomy status, they also include expanding the degree of autonomy, obtaining additional powers in certain policy areas, increasing opportunities for participation in decision-making at the national level (shared-rule), improving the quality of implementation of the autonomous status (if the actors are not satisfied with the de facto implementation of the autonomy status), etc. Therefore, regionalism should be defined more broadly: as a movement a movement that requires a region to be an autonomous actor in its relationship with the center.

The third connotation - regionalism as a model of relations between the center and the region, which is characterized by decentralization and regional autonomy - is a special kind of configuration of multilevel politics, when the regions already (to one degree or another) have political subjectivity. At the same time, the current configuration of multi-level politics is largely a product of the specific characteristics of individual countries / regions / sectors of politics, that is, it does not necessarily is influenced by regionalism. Likewise, the emergence of a regionalist movement is not necessarily a consequence of the specific nature of relations between the center and the regions. However, if there is a regionalist movement in the region, regionalists interact with the national and sometimes European levels of government to advance their demands. In doing so, they strive to ensure that the region would be more autonomous actor, that is, it behaves more actively and more independently. The main theoretical thesis of the project follows from this: regardless of whether or not regionalist demands are satisfied, the activities of regionalists change the configuration of multi-level politics, promote the autonomous involvement of regional actors in multi-level interactions, however, provided that the regionalist movement is an influential political actor.

Based on this thesis, the activities of the research team were aimed primarily at finding indicators that characterize the degree of autonomous involvement of regional actors in multi-level interactions. Careful examination of primary sources made it possible to determine such indicators as the activity of regions in the implementation of the right to legislative initiative at the national level and the right to appeal to national constitutional courts; involvement of regional actors in interaction with the bodies of the European Union, in the implementation of projects of the European territorial cooperation, in the functioning of Euroregions and some others. As a result, a database "Subnational regionalism and multilevel governance (REG-MLG)" was created. Originality and value of REG-MLG is determined, first of all, by the fact that, unlike existing databases and datasets, which provide information only about the institutional capacities of regions, the REG-MLG indicators allow measuring the implementation of institutional capacities, that is, the real involvement of regional actors in multi-level interactions. As regards the strength of regionalism, it was coded on the ground of the analysis of electoral statistics and documents of political parties, which made it possible to identify all significant regionalist parties (110 parties in 64 regions of European countries), that is, those that, firstly, have electoral activity in one (or several) regions, secondly, they put forward regionalist demands; thirdly, they received at least one seat in the regional parliament in 2 from the last three elections.

As a result of a series of quantitative large-N comparative studies that were conducted on the basis of REG-MLG using various methods of regression analysis, it was proved that the power of regionalism has a positive effect on the autonomous involvement of regional actors in multi-level politics. At the same time, depending on the arena and the sphere of interactions, in some cases, the influence of regionalism results in that the configuration of a multi-level politics is implemented in the format of intergovernmental relations (IGR), while in others, non-state actors are involved in interactions, and the configuration of a multi-level politics is more in line with the multilevel governance (MLG).

While confirming the main hypothesis as a whole, the study nevertheless convincingly proves that the influence of regionalism is not universal and all-encompassing, but rather sectoral and associated with other factors, and the strength of regionalism is by no means always the main factor, and in some cases even loses its significance. It depends, first, on the policy area in which the interactions take place. In some cases, the activity of a region is determined by its resource potential, in others - by institutional limitations. However, where resources and rules are not rigid constraints, and agent factors come to the fore, and the strength of regionalism becomes a significant factor. Secondly, the degree of influence of supranational structures. In some cases, the decisive factor is political and administrative regulation by the European Union. Third, country specificity can play a key role, that is, national patterns of multilevel policy.

A large-N quantitative analysis of the influence of regionalism on multi-level interactions in Russia (on the ground of Russian section of the REG-MLG) showed a connection between some indicators of regionalism and the activity of regions on draft laws and appeals to the court. However, this relationship is less significant and stable than in European countries. Unlike Europe, regionalism in contemporary Russia is not a kind of "holistic" phenomenon. Existing in a latent form, it manifests itself episodically, situationally, “pulsing” in the socio-political space.

Based on the empirical material collected during the project realization, including field studies, a series of comparative studies (qualitative small-N studies, QCA, case studies) were carried out. They made it possible to conclude that, although the mechanisms of the influence of regionalism on the autonomous activity of regional actors may be different, in European countries the activity of regionalist parties is of key importance. Therefore, the focus of research was to identify those characteristics of regionalist parties that affect its "strength", and through this, the autonomous involvement of regional actors in multi-level politics. As a result, it was established that, firstly, the constitutive foundations of regionalism and the intensity of regional identity are of key importance, and the most favorable option is when the ethnic specificity of the region is supplemented by a special geographical position and / or the specificity of historical development; secondly, the skillful legitimization of regional identity and regionalist demands; thirdly, the concentration of the ethnic minority in the region; fourthly, the moderate nature of regionalist demands and the compromise strategies of regionalist parties in inter-party interactions.

In Russia, where there are no regionalist parties, the results and fates of regionalist projects that were put forward in the early 1990s were examined. (Ural, Baltic, Pomor republics, Ingermanland, etc.). They were not implemented, but in a number of cases they impacted on the socio-political processes in the regions of the country. Comparative analysis showed that such a factor as a favorable configuration of actors (regional elites, activists, intellectuals), initiating and promoting the project, was of significant importance on the trajectory of their development. However, along with this, as in European cases, the legitimization of the project is fundamentally important.