General Pedro Santana had wrested the presidency from Buenaventura Báez, who had bankrupted the nation's treasury at great profit to himself. Faced with an economic crisis as well as the possibility of renewed attack from Haiti, Santana asked Spain to retake control of the country, after a period of only 17 years of independence. Spain was wary at first, but with the U.S. occupied with its own civil war and unable to enforce the Monroe Doctrine, it felt it had an opportunity to reassert control in Latin America. On March 18, 1861, the annexation was announced, and Santana became Governor-General of the newly created province.:202–04
However, this act was not well received by everyone. On May 2, General José Contreras led a failed rebellion, and Francisco del Rosario Sánchez led an invasion from Haiti (who were officially neutral, but also concerned about Spain flexing its muscles in the area), but he was captured and executed on July 4, 1861. Santana himself did not fare well under the new regime. He discovered that he was unable to wield the same amount of power under Spanish rule as he could as president of an independent nation, and resigned his post in January 1862.
Spanish officials began to alienate the general population by instituting a policy known as bagajes, which required citizens to hand over any work animals to the Spanish military upon demand without any guarantee of compensation. This was especially problematic in the Cibao region in the north, where farmers depended on their animals for their livelihoods. A second factor was cultural: the new archbishop from Spain was appalled to find that a large number of Dominican couples were not married within the Catholic Church. This situation had come about due to a small number of priests in the country, as well as poverty and the lack of roads and transportation to get to a church for marriage. With the best of intentions, Archbishop Bienvenido de Monzón wanted to rectify this situation within a short time, but his demands only irritated the local population, who had come to accept the current state of "illegitimate" births as normal.
Economically, the new government also imposed higher tariffs on non-Spanish goods and ships and attempted to establish a monopoly on tobacco, thus alienating the merchant classes as well. By late 1862, Spanish officials were beginning to fear the possibility of rebellion in the Cibao region (anti-Spanish feelings were not as strong in the south).:208–10 Lastly, despite explicit statements to the contrary, rumors spread that Spain would re-institute slavery and ship black Dominicans to Cuba and Puerto Rico.
Meanwhile, Spain had issued a royal order in January 1862 declaring its intent to regain the territories that Toussaint Louverture had taken for Haiti in 1794. In attempting to quell disturbances in Dominica, Spanish troops had evicted Haitians living in these areas along the Haitian–Dominican border. Haitian president Fabre Geffrard gave up his position of neutrality and began to aid the Dominican rebels.:210–11