During this period, two exceptions to the pattern of abbreviated rule were Faustin Soulouque (1847-59)... Soulouque, a black general of no particular distinction, was considered just another understudy when he was tapped by the legislature as a compromise between competing factions. Once in office, however, he displayed a Machiavellian taste for power. He purged the military high command, established a secret police force--known as the zinglins--to keep dissenters in line, and eliminated mulatto opponents. In August 1849, he grandiosely proclaimed himself as Haiti's second emperor, Faustin I.
Soulouque, like Boyer, enjoyed a comparatively long period of power that yielded little of value to his country. Whereas Boyer's rule had been marked by torpor and neglect, Soulouque's was distinguished by violence, repression, and rampant corruption. Soulouque's expansive ambitions led him to mount several invasions of the Dominican Republic. The Dominicans turned back his first foray in 1849 before he reached Santo Domingo. Another invasion in 1850 proved even less successful.
Santana responded to general discontent, prompted mainly by the deteriorating currency and economy, by resigning from the presidency in February 1848 and retiring to his ranch in the province of El Seibo. The Council of Secretaries of State, made up of former cabinet members, selected minister of war Manuel Jiménez to replace Santana in August 1848. Jiménez displayed little enthusiasm and no aptitude as a ruler. His tenure, which would probably have been brief in any case, ended in May 1849. The violent sequence of events that culminated in Jiménez's departure began with a new invasion from Haiti, this time led by self-styled emperor Faustin Soulouque. Santana returned to prominence at the head of the army that checked the Haitian advance at Las Carreras in April 1849. As the Haitians retired, Santana pressed his advantage against Jiménez. After some brief skirmishes between his forces and those loyal to the president, Santana took control of Santo Domingo and the government on May 30, 1849.
Although Santana once again held the reins of power, he declined to formalize the situation by standing for office. Instead, he renounced the temporary mandate granted him by the legislature and called for an election--carried out under an electoral college system with limited suffrage--to select a new president. Santana favored Santiago Espaillat, who won a ballot in the Congress on July 5, 1849; Espaillat declined to accept the presidency, however, knowing that he would have to serve as a puppet so long as Santana controlled the army. This cleared the way for Báez, president of the legislature, to win a second ballot, which was held on August 18, 1849.
Báez made even more vigorous overtures to foreign powers to establish a Dominican protectorate. Both France (Báez's personal preference) and the United States, although still unwilling to annex the entire country, expressed interest in acquiring the bay and peninsula of Samaná as a naval or commercial port. Consequently, in order to preserve its lucrative trade with the island nation and to deny a strategic asset to its rivals, Britain became more actively involved in Dominican affairs. In 1850 the British signed a commercial and maritime treaty with the Dominicans. The following year, Britain mediated a peace treaty between the Dominican Republic and Haiti.