1902: Civil war The government of Boisrond-Canal and General Nord Alexis fought Anténor Firmin’s rebel troops (Nord Alexis eventually prevailed and governed until 1908).
A list of the massacres in the 19th century amd the ongoing massacres of the 21st century are missing.
I wouldn't be surprised if in the Americas Haiti is the country with the most massacres on a per capita basis. Usually, massacres there tended to be focused on either people that were white or too light skin for the taste of whomever declared themselves emperors, kings, presidents, etc or people that were on the wrong side of politics vis-a-vis the politics of who was in power. Massacres committed on gangs gaining turf, money or any other reason is almost unheard of. This appears to be changing as per what is seen in this thread.
I think if you add all the victims of massacres committed in Haiti since 1804 to today would show that nowhere in this world has killed more Haitians than Haiti itself. Duvalier is assumed to be the deadliest dictator in the Caribbean with an estimated amount of victims that makes Trujillo's childs play and almost all of the victims of Duvalier were Haitians. More were the victims of Duvalier than the entire current population of Sosua (including Cabarete). The major difference is that now gangs are committing them, whereas before it was mostly the Haitian government.