Answer:
Preserving the Union.
Explanation:
Preserving the Union was one of the most important goals of Abraham Lincoln's presidency. This purpose was relevant throughout his presidency, including when he issued the Emancipation Proclamation. Lincoln believed that as president, it was his duty to ensure that the Union remained together. However, the Emancipation Proclamation was, to some extent, also motivated by the North's interest in eliminating slavery all over the country.
