was lincoln willing to compromise of the extension of slavery into territories
In office March 1861 - April 1865. Lincoln joined the Republican Party in 1856 and opposed the extension of slavery into new territories, though he could not see a way of abolishing it. His election as president precipitated the American Civil War. Lincolnâs aim was to preserve the Union, not to end slavery, which he made clear in his Gettysburg Address. However, as the war turned in the Unionâs favor in 1863 he proposed in his Emancipation Proclamation to free all slaves after the war.