American Civil War: The United States Congress passes the Crittenden–Johnson Resolution, stating that the war is being fought to preserve the Union and not to end slavery, in the wake of the defeat at the First Battle of Bull Run.

The American Civil War was a civil war in the United States between the Union and the Confederacy, which was formed in 1861 by states that had seceded from the Union. The central conflict leading to war was a dispute over whether slavery should be permitted to expand into the western territories, leading to more slave states, or be prohibited from doing so, which many believed would place slavery on a course of ultimate extinction.

The United States Congress is the legislative branch of the federal government of the United States. It is a bicameral legislature, including a lower body, the U.S. House of Representatives, and an upper body, the U.S. Senate. They both meet in the United States Capitol in Washington, D.C.

The Crittenden–Johnson Resolution was proposed in the United States Congress early in the American Civil War, as a conciliatory message to the slave states assuring them that the Northern war effort was not aimed at interfering with their rights to slavery, but solely towards restoring the Union. It was passed almost unanimously in July of 1861 after the shocking defeat at the First Battle of Bull Run. It was later rejected in December of that year during an attempt to reaffirm the resolution by congress.

The Union was the central government of the United States during the American Civil War. Its civilian and military forces resisted the Confederacy's attempt to secede following the election of Abraham Lincoln as president of the United States. Lincoln's administration asserted the permanency of the federal government and the continuity of the United States Constitution.