Costa Rica achieved its independence from Spain alongside other Central American countries or territories. **** "In 1821 a congress of Central American criollos declared their independence from Spain, effective on 15 September of that year. That date is still marked as the independence day by most Central American nations. The Spanish Captain General, Gabino Gaínza, sympathized with the rebels and it was decided that he should stay on as interim leader until a new government could be formed. Independence was short-lived, for the conservative leaders in Guatemala welcomed annexation by the First Mexican Empire of Agustín de Iturbide on 5 January 1822. Central American liberals objected to this, but an army from Mexico under General Vicente Filisola occupied Guatemala City and quelled dissent. When Mexico became a republic the following year, it acknowledged Central America's right to determine its own destiny. On 1 July 1823, the congress of Central America declared absolute independence from Spain, Mexico, and any other foreign nation, including North America and a Republican system of government was established." "Costa Rica's membership in the newly formed Federal Republic of Central America, free of Spanish rule, was short lived; in 1838, long after the Central American Federation ceased to function in practice, Costa Rica formally withdrew and proclaimed itself sovereign." Sources: http://en.wikipedia.org/wiki/History_of_Central_America http://en.wikipedia.org/wiki/Costa_Rica#History

When Mexico rebelled against Spain in 1821, Costa Rica benefited inadvertently and learned of its liberation a month after the fact. A faction in Costa Rica wanted to become part of Mexico and this sparked a civil war in Costa Rica between four neighboring cities. After the republican cities of San José and Alajuela defeated the pro-Mexican Heredia and Cartago, sovereignty was established. http://itravel-costarica.com/costaricahistory.html