Final answer:
Lincoln's Gettysburg Address outlines the Civil War's purpose to affirm liberty and equality, highlighting the sacrificial foundation of the United States' principles of democracy.
Step-by-step explanation:
According to Lincoln's Gettysburg Address, the purpose of the Civil War was to test whether a nation conceived in liberty and dedicated to the proposition that all men are created equal could endure. Lincoln articulated the main ideas of the document when he recognized the sacrifices made on the battlefield and reaffirmed the principles of equality and democracy as the foundation of the United States.
He emphasized that the Civil War was a means to secure a 'new birth of freedom' and ensure that a 'government of the people, by the people, for the people, shall not perish from the earth.'