La Trinitaria was a secret society that led the struggle to establish the Dominican Republic as a free, sovereign, and independent nation in the 19th century. They helped bring about the end of the Haitian occupation of the country in 1844.
La Trinitaria was established on July 16, 1838 by Juan Pablo Duarte in the house of Juan Isidro Pérez de la Paz. Some of its first members included Juan Isidro Pérez, Pedro Alejandro Pina, Jacinto de la Concha, Félix María Ruiz, José María Serra, Benito González, Felipe Alfau, and Juan Nepomuceno Ravelo. The society also conceptualized and designed the Flag of the Dominican Republic.
Duarte and his followers also founded the societies La Filantrópica and La Dramática, a more visible organization than La Trinitaria, which spread its separatist ideas by staging theatrical events. Unfortunately for the revolutionary movement and for Duarte, he was forced into exile in August 1843 as a result of his dissident activities.
La Trinitaria's other members continued the fight in Duarte's absence. One of them was Francisco del Rosario Sanchez, who corresponded with Duarte during the latter's exile in Venezuela, and Ramon Matias Mella, who along with Duarte and Sanchez became known as the founding fathers of the Dominican Republic.
On January 16, 1844 La Trinitaria's manifesto in favor of independence was released, and the fight for independence began to gain the necessary momentum. On the heels of La Trinitaria's work, and after many battles and much bloodshed, the Dominican Republic was born on February 27, 1844, claiming independence from Haiti with a declaration at the Puerta del Conde.
The involvement of La Trinitaria is also seen in the early formation of the new Republic. Yet, for the most part the society's ideology, which was in sync with Duarte's, was not implemented, as Pedro Santana forcibly took the reins of the newly formed nation and exiled Duarte. As a result, Santana enacted re-colonization of the country by Spain, making it the only former colony of the Americas to do so.
Other usage 
Today, La Trinitaria may also refer to the three founding fathers of the Dominican Republic. The usage is a play on words whereby the concept of the Trinity is overlapped with the establishment of one nation by the three founding fathers: Duarte, Sánchez, and Mella.
- "Juan Pablo Duarte Square". NYCGovParks.org. 2000. Retrieved 2010-07-26.