The significant figure known for his role in the founding of the United Nations is Dag Hammarskjöld, who served as the organization’s second Secretary-General from 1953 until his death in 1961. His commitment to international peace and security helped shape the UN’s framework for addressing global conflicts. Hammarskjöld promoted the concept of the UN Peacekeeping Forces and was instrumental in fostering dialogue among nations during the Cold War era. His legacy continues to influence current discussions on global governance and diplomatic efforts.