On 1 May 1961, Brigade 2506—Cuban exiles trained and equipped by the U.S. Central Intelligence Agency—landed at Cuba’s Bay of Pigs (Playa Girón and Playa Larga) with the objective of overthrowing Fidel Castro’s government. The operation, conceived during the Eisenhower administration and inherited by President John F. Kennedy, was intended to spark an internal uprising and prompt the collapse of Castro’s revolutionary regime. The invasion encountered immediate and severe problems. From the outset, plans relied heavily on secrecy and the expectation of limited, deniable U.S. military involvement. That calculus changed into a critical liability when promised air support and broader military intervention did not materialize in the form and scale needed. Political concerns in Washington about overt U.S. action, fears of international escalation, and a desire to preserve plausible deniability constrained the level of direct U.S. participation. Operational shortcomings compounded the political constraints. Intelligence underestimated the strength, cohesion, and preparedness of Castro’s armed forces in the region. The landing sites were exposed to rapid counterattack, and the invading forces lacked secure supply lines and robust logistical backing. Poor communications, inadequate consolidation of beachheads, and the failure to secure key nearby airfields left the invaders vulnerable. Cuban government forces—regular army units supplemented by militia and local volunteers—responded quickly and effectively. Cuban air and ground forces attacked the invasion beaches, interdicted reinforcements and supply routes, and encircled the exile brigades. Within 48 to 72 hours the invaders were pinned down. Efforts to evacuate or extricate forces were hampered by the operational environment and by Washington’s reluctance to deploy overt U.S. military assets. Casualties and captives mounted. Hundreds of Brigade 2506 members were killed or wounded in combat; many more were captured. Cuban authorities held captured fighters as prisoners of war; in the weeks and months that followed, most were eventually released in a negotiated prisoner exchange for food and medical supplies paid for by international intermediaries, notably including Catholic Charities and other organizations. The political fallout was immediate and significant. The failed invasion damaged the Kennedy administration’s credibility and demonstrated the risks inherent in covert paramilitary operations that lack clear political and military backing. Internationally, the episode strengthened Castro’s position in Cuba and provided the government with propaganda value portraying the revolution as under threat from U.S.-backed aggression. It also contributed to the deterioration of U.S.-Cuban relations and fed a cycle of mutual distrust that would influence subsequent crises, most notably the Cuban Missile Crisis in 1962. Historians have examined multiple causes for the collapse: unrealistic assumptions about popular uprisings, underestimation of Castro’s forces, flawed operational planning, and miscommunications between Washington and field commanders. The Bay of Pigs remains a case study in the limits of covert action, the perils of political constraints on military operations, and the unintended consequences that can follow a failed attempt to change another country’s government. While facts about troop movements, casualty counts, and diplomatic exchanges are well documented in declassified U.S. government records and contemporary reporting, interpretations of decision-making in Washington and Havana vary among scholars. There is broad agreement, however, that the invasion’s quick collapse was decisive in shaping U.S.-Cuban relations for years to come.