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12.4 The Filibuster and the Quest for New Slave States

🗽US History
Unit 12 Review

12.4 The Filibuster and the Quest for New Slave States

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
🗽US History
Unit & Topic Study Guides

Southern expansionism in the mid-19th century was driven by a desire for new slave states and economic opportunities. Southerners sought to maintain political power and expand slavery, justifying their actions with Manifest Destiny and beliefs in Anglo-Saxon superiority.

Filibuster expeditions, like those led by Narciso López and William Walker, strained international relations and sparked domestic debates. These unsanctioned invasions violated laws, risked war, and deepened the growing divide between North and South over slavery's expansion.

Southern Expansionism and Filibustering

Motivations for southern expansionism

  • Southern desire for new slave states driven by the need to maintain balance of power in the Senate and protect and expand slavery as an institution
  • Economic motivations included acquisition of new lands suitable for plantation agriculture (cotton, sugar) and access to resources and markets in Latin America and the Caribbean
  • Ideological justifications rooted in Manifest Destiny and the belief in Anglo-Saxon superiority, as well as a perceived "civilizing mission" to spread slavery and southern culture

Impact of filibuster expeditions

  • Strained relations with targeted countries, particularly Cuba and the Spanish Empire, as well as Nicaragua and other Central American nations
  • Violation of international law and neutrality acts, as filibusters acted without official U.S. government support, leading to diplomatic challenges and potential for war
  • Domestic political divisions, with northern opposition to filibustering and southern expansionism, and debates over the morality and legality of filibustering expeditions

Key figures in territorial acquisitions

  • Narciso López and the Cuban expeditions (1849-1851)
    • Attempted invasions to annex Cuba as a slave state, garnering support from prominent southern politicians and wealthy planters
    • Ultimate failure and execution of López by Spanish authorities
  • William Walker and the Nicaraguan campaign (1855-1860)
    • Briefly served as president of Nicaragua after a successful filibuster expedition, attempting to establish a pro-slavery government and attract southern colonists
    • Overthrown by a coalition of Central American countries and executed in Honduras

The Filibuster Movement's Legacy

Motivations for southern expansionism

  • Filibustering as a manifestation of southern nationalism, with attempts to create a "Golden Circle" of slave states in the Caribbean and Central America
  • Resistance to perceived northern dominance and anti-slavery sentiment
  • Filibustering's impact on sectional tensions, intensifying the north-south divide over the issue of slavery's expansion and contributing to the growing polarization that ultimately led to the Civil War

Impact of filibuster expeditions

  • Damage to U.S. reputation abroad, with the perception of the U.S. as an aggressive, expansionist power, undermining efforts to establish peaceful relations with Latin American countries
  • Strengthening of anti-American sentiment, leading to resistance to U.S. influence and interventionism in the region and laying the foundation for future conflicts and mistrust between the U.S. and Latin America

Key figures in territorial acquisitions

  • Legacy of López and Walker as controversial figures, celebrated by some as heroes of southern expansionism and manifest destiny, while condemned by others as reckless adventurers and agents of slavery
  • Enduring impact on popular culture and historical memory, with representation in literature, film, and other media, and ongoing debates over their actions and motivations as reflections of larger political and social issues in the antebellum era

Sectionalism and the Quest for New Slave States

  • Growing divide between North and South over slavery's expansion and economic interests
  • Southern efforts to maintain political power through the acquisition of new slave states
  • Impact of sectionalism on foreign policy and territorial expansion, influencing filibuster expeditions and diplomatic relations with Latin American countries