Urban energy transitions as responses to climate change imperatives have become a significant means in local politics and sustainability strategies. This paper seeks to understand the complexity of actions, relations and local dependencies within the governance of urban energy systems in shaping the transition processes. We present an analytical framework engaging the governance aspects with characteristics of material-related political processes, and apply it to our case study of the city of Hamburg, Germany. We interrogate the city's transition pathway in the context of local energy-climate politics, general aspects of the German energy transition, and energy materiality. This paper builds up understandings of path dependencies by exploring the inter-relations between important elements of the urban energy system and the material-related political processes in a learning context. Drawing on the Hamburg case, we suggest a more context-specific way to outline the different motives, interests and powers of actors/coalitions in cities. This paper reveals the learning and experimenting capacities of actors as a means of understanding the conditions and roles of cities to make structural changes for transition. Finally, city-driven transitions should further expand from the translation of ‘global problem, local solution’, to a more local-oriented focus. The notion of locality highlights that urban energy transition is creating a special political arena with its own and self-regulated dynamics, and resulting in local solutions for both the governance mode and materiality of the urban energy system.