This study advances the argument that democratization is best understood as the outcome of a reciprocal interaction between political culture, institutional arrangements, and geopolitical contexts, rather than as an outcome of fixed cultural or religious determinants. Conceptualizing political culture as a dynamic system of orientations shaped by historical experience, spatial location, and regional security environments, the paper integrates political culture theory with geopolitical and political–geographical analysis. Drawing on comparative illustrations from Eastern Europe, the MENA region, Southeast Asia, and Latin America, the study demonstrates that similar cultural or religious backgrounds generate divergent democratic trajectories depending on institutional mediation and exposure to external geopolitical pressures. The findings directly challenge cultural determinist explanations particularly those attributing democratic failure to Islam or Arab culture by showing that religion operates through political institutions and geopolitical constraints rather than as an independent causal variable. This geopolitically grounded framework offers a coherent explanation for democratic divergence and contributes to comparative political theory by reconceptualizing political culture as contingent, adaptive, and context-dependent.