After losing the support of Haiti's elite, Boyer was ousted in 1843, with Charles Rivière-Hérard replacing him as president. Nationalist Dominican forces in eastern Hispaniola led by Juan Pablo Duarte seized control of Santo Domingo on 27 February 1844. The Haitian forces, unprepared for a significant uprising, capitulated to the rebels, effectively ending Haitian rule of eastern Hispaniola. In March Rivière-Hérard attempted to reimpose his authority, but the Dominicans put up stiff opposition and inflicted heavy losses. Rivière-Hérard was removed from office by the mulatto hierarchy and replaced with the aged general Philippe Guerrier, who assumed the presidency on 3 May 1844.