Duarte, who was sent to Europe for his education (1828–33), became determined to free the eastern part of Hispaniola from Haitian domination. On his return to the island he and several other patriots organized a secret society, La Trinitaria, to work toward independence and to stimulate liberalism. His first attempt to oust the Haitians in 1843 collapsed, and he fled the country; but his followers succeeded in overthrowing the Haitians the next year.

In February 1844 Duarte returned, and the Dominican Republic proclaimed its independence. It was not Duarte's followers, however, who ultimately triumphed, but a local caudillo (military dictator), Pedro Santana. The defeated Duarte was exiled and took up residence in Caracas, Venez. He left Caracas for his homeland only once, during the War of Restoration (1864) against Spain, after which he was sent on a diplomatic mission for one year.