This dissertation addresses the problem of the sources of associational life and civic engagement. I develop a new theory of the origins of associational life by a comparative historical study of popular sector/lower class associations of urban and rural populations in a set of Western European countries during the period of the 1870s-1970s. The countries under study are Sweden, Norway, Austria (strong civil society); Germany, Netherlands, Belgium (medium to high associatonal life); Britain (medium associational life); Italy, France, Spain and Portugal (weal to very weak associational life). Three political and institutional factors have shaped civil society: 1) Timing of state building and/or international status in the eighteenth and nineteenth centuries. The latter the process of state building and/or the lower international status in the eighteenth and nineteenth centuries, the stronger will be political parties and civil society organizations in the twentieth-century. In states that consolidated fully during the mid and late nineteenth-century and/or had been secondary states in the international system in the eighteenth-century, the pre-modern corporatist structures (e.g. guilds, religious corporate bodies) survived up to the early twentieth-century, because the pressures for resource extraction from state-builders were weaker. This in turn promoted a stronger popular sector organizational life in the late nineteenth and early twentieth centuries. 2) State-capacity: the stronger state capacity, the stronger will be voluntary associations. States with high capacity are able to implement policies and establish goals autonomously decided by rulers. In the late nineteenth-century, one of the main functions of the state became the promotion of economic development and nationalist mobilization. For this purpose states have established partnerships with associations. This has empowered associations, through two mechanisms. First, associations have received resources, legitimacy and public status from the State, being thus able to recruit more members through the distribution of selective benefits (welfare, pensions). Second, since high capacity states are more able to impose a uniform jurisdiction and control over a territory, this will make easier for associations to expand through the whole national territory, to connect different geographical areas and more easily develop encompassing peak associations. 3) Democratization: the stronger the degree of democratization of the regime between the 1880s and the 1930s, the stronger associational life. Democratization is measured by two dimensions: 3.1) the extension of rights of participation, debate, and assembly; 3.2) the degree of parliamentarization of the regime. This refers to the control by representative bodies of the formation, decisions, personnel and policies of the executive. The stronger the parliament, the more associational leaders will seek to influence and establish links with MPs and political parties and build their own agenda according to parliamentary cycles. Since strong parliaments represent the whole nation, associations will tend to become national in scope, and as such more coordinated through the territory, with associational leaders creating links and alliances that run through several regions of the country. Moreover, in a strongly parliamentarized system parties will be also more interested in creating permanent and not episodic links with associations in order to have a higher reach to the electorate.