Although conflict-affected populations are often exposed to and severely impacted by disasters, little is known about their perceptions and practices concerning Early Warning and Early Action (EWEA) or how EWEA strategies can protect communities affected by conflict- and climate-related disasters. This is particularly problematic as, due to the multiple challenges posed by conflict and compound crises in these contexts, early warnings of weather hazards do not often translate in early actions. This comprehensive literature review examined 384 peer reviewed papers produced between 2004 and 2022, focused on the twenty countries most affected by non-international armed conflict and exposed to climate hazards. This paper answers the question: What is the state of knowledge of EWEA for climate hazards in countries affected by armed conflict and high levels of forced displacement? Findings demonstrate that most research focuses on climate science rather than social science across six elements of the EWEA value chain: 1. hazards analysis, 2. understanding vulnerability and exposure, 3. warning communication and dissemination, 4. forecasting availability and monitoring, 5. early action planning, and 6. financing systems. In total, 75.65% of the research studies focused on hazard analysis, forecast availability, and monitoring. There has been a strong increase in academic research on EWEA in conflict-affected countries since 2004. However, we identify that most of this research has been in Ethiopia, Pakistan, and Nigeria which, although severely affected by conflict, also have a higher level of economic development and stability. In contrast, there is little research focused on EWEA in most of the remaining countries. Across all thematic areas, there is a lack of consideration of conflict dynamics in EWEA research. This paper contributes to evidence on the need to recognize people affected by conflict in disaster risk reduction, as called for in the Sendai Framework for Action midterm review, with the aim of enhancing EWEA investments to enable tailored approaches appropriate for conflict-affected states.