Southern Slavery, Northern Freedom: The Central Dilemma of the Republic
I cannot imagine that any European power would dare to recognize and aid the Southern Confederacy if it became clear that the Confederacy stands for slavery and the Union for freedom.
President Abraham Lincoln, September 1861
[Emancipation is] a military necessity, absolutely essential to the preservation of the Union.
President Abraham Lincoln, July 13, 1862
Despite the Lincoln administration's efforts to focus on Union as the central purpose in the war, slavery became a vital consideration in both British and French thoughts about intervention. Ironically, however, the role of slavery in these foreign deliberations proved far different than assumed in Washington. The peculiar institution, as the White House correctly observed, emerged as a formidable obstacle to British involvement in the war. But it also played another unexpected role. Many British observers feared that Lincoln was prepared to announce emancipation in an effort to instigate slave insurrections aimed at destroying the South from within. Most ominous, they believed, such uprisings would develop into a race war that crossed sectional boundaries and ultimately hurt those nations dependent on goods from both North and South. The French situation was likewise more complicated than depicted by contemporaries. The public opposed slavery and hence had an initial affinity for the Union, but Napoleon had more important objectives unrelated to that issue. He wanted to build a commercial empire in the Americas that started with his establishing control over Mexico and depended heavily on a friendly and independent Confederacy to contain U.S. expansion. Both Britain and France, however, found it impossible to ignore the influence of slavery in nearly all matters affecting the American war.
Regardless of the issue at almost any time in the diplomacy of the Civil War, slavery almost always wound itself into the mix. The reason was clear: