General Francisco Mejia was a Mexican general. He started his military career at the age of 15 in the Spanish colonial army. His first major battle was in Mexico's war of Independence in 1821 and he also fought when Spain invaded Mexico in 1829. The Battle of San Jacinto occurred in 1836 and was won by the Texans, allowing them to become an independent nation until they became part of the United States in 1845.