IB History: The American Civil War — notes, maps and essay questions

Chapter 1: Manifest Destiny and the Mexican War

Land hunger and an ideology of destiny. The brown arrow follows the Oregon Trail, traveled by thousands in the 1840s. As settlers moved west, they looked to Washington to secure the land they entered. Expansionists gave the movement a larger meaning through Manifest Destiny: Providence had supposedly assigned the continent to the United States. Pacific ports promised trade with China, while racial ideas encouraged the belief that Mexicans and Native peoples should give way.

Polk’s determination to have California. Polk took office in 1845 determined to acquire California, whose harbors at San Francisco and San Diego offered access to the Pacific. He first sent John Slidell to Mexico City, authorized by most accounts to offer up to $25 million. Mexico refused to receive him. Polk then sent Taylor’s army to the Rio Grande, into land held by Mexico and claimed by Texas. An attempt to buy territory had given way to an armed standoff.

A Mexican state at its weakest. Mexico had little room to respond to Polk. Its treasury was empty, generals made and unmade governments, and Comanche and Kiowa raids had devastated northern states. A leader who discussed selling land risked overthrow: Paredes toppled Herrera after Herrera showed willingness to talk. Mexico was poorly placed both to deter the United States and to bargain with it.

Texas and the politics of slavery. The argument over Texas was also an argument over slavery. In 1844 Calhoun told the British minister that annexation would protect it from British abolitionism; the Senate rejected the treaty that June partly for that reason. Texas entered as a slave state by joint resolution in 1845. Northern opponents saw the “slave power,” their name for slaveholders’ supposed control of federal government, extending its reach. When war brought the prospect of still more territory, that suspicion followed it into Congress.

Chapter 2: A House Dividing

Slavery as capital, not merely labor. A person enslaved in Virginia could be sold to a buyer in Mississippi or another area open to slavery. Demand from such markets sustained the value slaveholders assigned to people they claimed as property. Expansion offered political protection too, through new slave states. Closing the frontier threatened both expectations, although historians differ about how quickly containment would have weakened slavery.

Two economies, two civilizations. Factories, railroads, public schools, and immigrant cities grew in the free states. The South’s highly profitable plantation economy depended on enslaved labor. Each section accused the other of betraying the Founders. Disputes over tariffs, homesteads, and railroads could thus become entangled with the future of slavery and the balance of power between the sections.

The machinery of compromise breaks. Earlier bargains had given each section something it could accept. Kansas–Nebraska removed the Missouri Compromise’s fixed boundary at 36°30′; Dred Scott then held that Congress could not exclude slavery from territories at all. The institutions needed to negotiate a new bargain were under strain as well. In 1856 Senator Charles Sumner was caned on the Senate floor, making the chamber itself a scene of violence.

The sectional math of 1860. Population growth gave the free states enough electoral strength to choose a president on their own. Lincoln’s 1860 victory demonstrated it: he carried every free state and lost every slave state. Southern leaders now faced the prospect of continuing in the Union as a political minority. Secession was partly a refusal to accept both that prospect and the immediate election result.

Chapter 3: Secession Winter

A four-month vacuum of power. Before Lincoln’s March inauguration, Buchanan faced states claiming to have left the Union. He considered their action illegal, but denied that coercion was lawful. That left the federal government without a policy for stopping them as Deep South leaders seized forts and arsenals and organized a government. Lincoln inherited an established claim to authority backed by institutions and territory.

The secessionists’ own words. Why did the secessionists act? Their own declarations place slavery at the center. Mississippi stated: “our position is thoroughly identified with the institution of slavery, the greatest material interest of the world.” Alexander Stephens, the Confederate vice-president, described slavery as the “cornerstone” of the new state. Later accounts offered different explanations, but these founders made their commitment explicit.

Sumter as a designed dilemma. Lincoln’s provision mission made the presence of the federal flag at Sumter Davis’s immediate problem. Let the food through, and the garrison could remain in Charleston harbor; fire, and Northerners could see the Confederacy as responsible for opening hostilities. Davis hoped a confrontation would bring in the Upper South. It did, but the attack also helped unite a divided North behind the Union.

Why the border stayed. Lincoln needed the border states and treated them with both force and restraint. He suspended habeas corpus in Maryland and accepted a rump legislature in Missouri. Kentucky’s declared “neutrality” he left alone until Confederate troops occupied Columbus. He is said to have remarked, “I hope to have God on my side,” and “but I must have Kentucky”. The states that stayed supplied the Ohio River line, Missouri’s rivers, roughly 400,000 white men of military age and, later, tens of thousands of Black recruits.

The Union and abolition endure. Secession had been argued as a constitutional possibility. The war settled that struggle by force, and no state has seceded since. The Thirteenth Amendment abolished slavery, except as punishment for crime after conviction, and remains part of the Constitution. These settlements endured at an immense cost, even as Americans continued to dispute what freedom should mean in practice.

Citizenship remains contested. A constitutional promise of citizenship leaves many practical questions to be answered. Who can vote, attend school, serve on a jury or hold a property deed? From Colfax to Selma, Black Americans pressed claims recognized by the wartime amendments but not secured in daily life by their words alone. A map of twentieth-century civil rights belongs beside this one: its geography shows the struggle over that settlement continuing across the South. The planned civil-rights atlas is a sequel in spirit.

Follow a change on the map. In Free Explore, scrub from 1861 to 1865 and choose one change to follow. You could watch the Mississippi close, trace the border-state belt that never flips, or follow the hatched guerrilla country that no army pacified. Charleston harbor offers a route from the first shell at Sumter to the flag raised again there on 14 April 1865. That same day Lincoln was shot at Ford’s Theatre. Each route brings a particular geography into the larger story of the war.