Culture occupies an increasingly visible place in contemporary International Relations (IR), yet its theoretical status remains unsettled. While scholarship on constructivism, Global IR, cultural diplomacy, international order, and postcolonial approaches has demonstrated that meanings, identities, norms, and historical experiences shape international politics, culture is still frequently approached as a contextual variable, a resource of state influence, or a source of national identity. This article argues that such approaches do not fully capture the constitutive role of culture in international political life. Culture is not simply something that states possess or mobilise; it contributes to the formation of interests, identities, legitimacy, authority, status, and understandings of international order. Drawing on recent scholarship on cultural diplomacy, cultural heritage, relational approaches to IR, and the pluralisation of international theory, the article develops the concept of cultural relationalism as a framework for understanding how international actors construct political meaning through historically and culturally embedded relationships. The argument also addresses the dangers of cultural essentialism. Recognising cultural plurality should not require treating societies as internally homogeneous or assuming that non-Western perspectives are inherently more authentic than Western ones. Instead, culture should be understood as dynamic, contested, relational, and politically consequential. The article therefore proposes a culturally relational approach to IR that moves beyond both Eurocentric universalism and simplistic cultural relativism. Keywords: culture; international relations; cultural relationalism; Global IR; identity; international order; postcolonialism; cultural diplomacy