This thesis lays focus on the Young Socialist Movement (ungsocialisterna) and their mobilisation in Stockholm between 1903 and 1910. In line with social movement research the theoretical concepts of mobilisation structure and resource mobilisation are used to examine the Young Socialists local clubs mobilisation and its prerequisites. The results show that the mobilisation structure of the Young Socialists in Stockholm was characterised by a fragmented organisational framework, wherein local clubs operated independently. This underscored the importance of the groups social network in their mobilising efforts and collaboration between the clubs. The ideological stance was ambiguous, and various radical ideas influenced the mobilisation structure of the group. Due to a lack of tangible resources, human and intangible resources played an essential role in the Young Socialists mobilisation efforts. Over time the decentralised organisational structures and diverse ideological affiliations came to hinder the Young Socialists effectiveness in mobilising towards their goal: the socialist revolution. This study sheds light on the practices and mobilising process of an often overlooked group that was highly influential in shaping the early labour movement in Sweden. It also underscores the importance of a unified mobilisation structure for social movements.