Why did Guatemala oppose Belizean independence?

Guatemala’s opposition to Belizean independence was rooted in a long-standing territorial dispute based on the claim that Guatemala had inherited Spanish interests in the region.12

Although Great Britain and Guatemala attempted to resolve their differences through an 1859 treaty that defined boundaries, the relationship became increasingly strained. The dispute turned intractable after 1940, when Guatemala declared the 1859 treaty null and void, arguing that a provision requiring both parties to establish "the easiest communication" between the two territories had never been fulfilled.12

This unresolved territorial claim led to "unrelenting Guatemalan hostility," which significantly impeded Belize’s path to independence during the mid-20th century. Despite this pressure, Belize pursued self-determination through the international community, eventually achieving independence in 1981 with a British defense guarantee. Guatemala did not formally recognize Belize as an independent state until the early 1990s, and the two nations have since agreed to submit their ongoing border dispute to the International Court of Justice for a final legal resolution.34