9. An attempt by the province of Yucatán to declare independence from the Mexican Federation, the Republic of Yucatán defeated their larger rival militarily but later succumbed to severe economic pressures
Initially existing briefly between May 29, 1823, and December 23, 1823, as the Federated Republic of Yucatán, the short-lived entity became one of the founding members of the United Mexican States following its transition from a monarchy into a republic. Swearing to recognize the government of Mexico “only if it is liberal and representative”, even whilst enthusiastically entering, Yucatán warily laid the groundwork for a future secession and retained the right to “form their particular Constitution” if necessary. Following the increased centralization of power and loss of autonomy, after being denied return to federalization Yucatán declared independence in February 1840.
Led by the commander of the federal army in Yucatán, the separatists quickly seized control over the territory and formally proclaimed the Republic of Yucatán once again on March 13, 1841. Instituting one of the most progressive constitutions of the age, including the abolition of conscription and provisions for religious liberty, Mexico responded by declaring war. Failing to invade the Yucatán Peninsula, sending four thousand soldiers to discover almost fifteen thousand waiting for them, Mexico responded by blockading their new neighbor. Causing economic turmoil throughout the republic, as a result of the Caste War with indigenous Mayans, Yucatán was forced to accept military aid from Mexico and rejoin the Federation.