Belize–Mexico border

The Belize–Mexico border is an international border between Belize and Mexico. It is 250 km (155 mi.) long and almost exclusively follows the course of the Hondo River. It separates Belize from the Mexican states of Quintana Roo and Campeche.

The modern boundary was agreed to in 1893, and finalized in 1897.

The border between Mexico and Belize was difficult to explore because of its remote location, specifically for the Mexican territory. Because of the region's sparse population, the British colony of British Honduras, now Belize, was able to occupy the region. However, Mexico did not recognize British possession of the territory until the late nineteenth century. The Mexican government wanted to diminish, and eventually end, arms smuggling from Belizean Maya supplied by rebels during the Caste War, which prolonged the situation.

As a result, the government of Porfirio Diaz created a Federal Territory which had previously belonged to the State of Yucatan. They later formed the Territory of Quintana Roo and decided to negotiate with the British government to finally fix the common border. They agreed to recognize British governance for the territory in return for Britain's promise to refrain from arming the Maya. With respect to these intentions, Mexico appointed Ignacio Mariscal, Secretary of Foreign Affairs, as Minister Plenipotentiary and the United Kingdom appointed Sir Spenser St. John to its Minister Plenipotentiary in Mexico for negotiations.

A treaty was signed on July 8, 1893, in Mexico City, and an additional convention added on April 7, 1897. The original treaty consisted of four articles; the first set the upper border, the second required Great Britain to stop arming Mayan rebels, the third laid out the obligation of both states to prevent Native Americans from gradually encroaching into the territory of the neighboring country, and the fourth required ratification of the treaty by the respective governments.

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