The United States began its occupation of Haiti after a series of political upheavals in the early 20th century, notably the assassination of President Vilbrun Guillaume Sam. The political instability posed a threat not only to the safety of American nationals in Haiti but also to the strategic and economic interests of the United States in the Caribbean. In response, U.S. President Woodrow Wilson authorized the deployment of Marines to stabilize the region. The Marines landed in Port-au-Prince on July 28, 1915, and quickly took control of the country’s key installations and government functions.

The U.S. occupation was characterized by military governance, as American authorities implemented significant changes to Haiti's infrastructure, economy, and political system. The U.S. established a new constitution and controlled Haitian finances through the Haitian National Bank, pushing for economic modernization. These actions were met with resistance from many Haitians, who viewed the occupation as an infringement on their sovereignty and an imposition of foreign control. The period saw outbreaks of violence and resistance against American rule, leading to conflicts like the Caco Wars.

The occupation lasted until 1934 and had lasting effects on Haiti, including the establishment of a more centralized administrative system and the promotion of broader educational initiatives. However, the military approach often stifled local governance and incited a complex legacy of dependency and resentment among Haitians towards the United States. The political structures and the economic policies put in place during this period have had long-term implications for Haiti’s subsequent history, including later upheavals.