In the quest for (more) effective adaptation, demands are rising in adaptation policy practitioners to address systemic injustices. In practice, however, adaptation incrementalism dominates, i.e. small-scale, reactive solutions, especially as it relates to addressing vulnerable populations. Germany is exemplary of these tensions. Little research investigates the larger context factors which impede the root causes of vulnerability from being addressed, how to transition away from incrementalism, and the role environmental agencies can play in this. Applying historical materialist policy analysis, the article follows a three-step approach which examines context, actors, and processes. The context analysis demonstrates how effective means for social redistribution were reduced since the mid-1980s in Germany’s capitalist welfare state. This corresponds with heightened social vulnerability to climate change. The actor landscape is diversifying. In the past, social policy actors (and tasks) were underrepresented but are becoming more important. The policy process indicates a greater focus on vulnerable populations. Yet, the understanding of the structural root causes of peoples’ vulnerability and financial resources of the policy field remain limited. This corresponds with informatory instruments of shallow depth. An improved root cause analytic coupled with new alliances and policy mixes are a good starting point towards greater social justice in adaptation.