This thesis examines dynamics of statebuilding and social mobilisation in Afghanistan from 2001 to 2016 and seeks to contribute to two sets of scholarly literature. First, it aims to contribute to better understanding of the complexity of the post-2001 international intervention and statebuilding in Afghanistan. Second, it aims to contribute to broader literature on contentious politics by extending its theoretical insights to explore dynamics of social movements in the context of a fragile state The thesis investigates how state fragility, characterised by weakness in extending its authority, in providing public services, and in developing effective and legitimate institutions, can shape contentious politics, and whether state weakness creates conditions that benefit some movements over others. It combines a relational and mechanism-based approach with a multi-institutional view of politics and society and highlights the nature and dimensions of change and conflict. This is achieved by studying four groups and three protest events in Afghanistan. Through detailed analysis of the four groups, which provide examples of broadly liberal, left-leaning and Islamist movements in the country, as well as analysis of three mass protest events, the thesis argues that the character and strength of the state has a number of important implications for contentious politics. First, while the institutions of liberal democracy, and parallel processes of exposure of Afghan society to globalisation between 2001 and 2016, helped give rise to a new generation of activists, the highly-centralised institutional structure combined with institutional discouragement of political parties and predominance of patron-client relations drove a new generation of activists towards street politics. Consequently, the neopatrimonial character of the state and dominance of patron-client relations discouraged a younger generation of activists from directly participating in the affairs of state. Second, based on the type and level of statebuilding programmes and policies, the thesis identified four responses by the case study groups towards the post-2001 international intervention and statebuilding process: reformist, transformationist, rejectionist and partial rejectionist. These case studies show that while these groups tend to be ideologically oriented towards certain strategic responses, in general policy-level contention and social movement formation were undermined by deeper programmatic and foundational conflicts. Furthermore, these group-level responses were the outcomes of collective attribution of threats and opportunities in a strategic environment that was shaped by a multitude of actors, including non-state and anti-state actors. Mass protests were closely linked to a period of particular decline in state authority and capacity to provide security and services from 2014 to 2016. The three protest events, the largest of their kind during this period, were collective responses to state failures to provide security and basic public services. Finally, while the Islamists have tended to be more successful in building organisations and reaching out to masses and even assuming some state-like functions such as providing services, it was not clear that these organisational gains would necessarily lead to political advantages as in winning elections. Furthermore, the more successful Islamist organisations also appropriated a wide range of secular socio-economic and political responses which may shape their long-term political orientations.