The Ephemeral Independence and Haitian occupationJosé Núñez de Cáceres, declared the colony's independence, on November 30, 1821. He requested the new state's admission to Simón Bolívar's republic of Gran Colombia, but Haitian forces, led by Jean-Pierre Boyer, invaded just nine weeks later, in February 1822.
As Toussaint Louverture had done two decades earlier, the Haitians abolished slavery. But they also nationalized most private property, including all the property of landowners who had left in the wake of the invasion; much Church property; as well as all property belonging to the former rulers, the Spanish Crown. Boyer also placed more emphasis on cash crops grown on large plantations, reformed the tax system, and allowed foreign trade. But the new system was widely opposed by Dominican farmers, although it produced a boom in sugar and coffee production. All levels of education collapsed; the university was shut down, as it was starved both of resources and students, since young Dominican men from 16 to 25-years-old were drafted into the Haitian army. Boyer's occupation troops, who were largely Dominicans, were unpaid, and had to "forage and sack" from Dominican civilians. Haiti imposed a "heavy tribute" on the Dominican people.:page number needed Many whites fled Santo Domingo for Puerto Rico and Cuba (both still under Spanish rule), Venezuela, and elsewhere. In the end the economy faltered and taxation became more onerous. Rebellions occurred even by Dominican freedmen, while Dominicans and Haitians worked together to oust Boyer from power. Anti-Haitian movements of several kinds — pro-independence, pro-Spanish, pro-French, pro-British, pro-United States — gathered force following the overthrow of Boyer in 1843.:page number needed
IndependenceJuan Pablo Duarte founded a secret society called La Trinitaria, which sought the complete independence of Santo Domingo without any foreign intervention.:p147–149 Ramón Matías Mella and Francisco del Rosario Sánchez, despite not being among the founding members of La Trinitaria, were decisive in the fight for independence. Duarte and they are the three Founding Fathers of the Dominican Republic. On February 27, 1844, the Trinitarios (Trinitarians), declared the independence from Haiti. They were backed by Pedro Santana, a wealthy cattle rancher from El Seibo, who became general of the army of the nascent Republic. The Dominican Republic's first Constitution was adopted on November 6, 1844, and was modeled after the United States Constitution.
The decades that followed were filled with tyranny, factionalism, economic difficulties, rapid changes of government, and exile for political opponents. Threatening the nation's independence were renewed Haitian invasions occurring in 1844, 1845–49, 1849–55, and 1855–56.:page number needed
Meanwhile, archrivals Santana and Buenaventura Báez held power most of the time, both ruling arbitrarily. They promoted competing plans to annex the new nation to another power: Santana favored Spain, and Báez the United States.