The Civil War made a huge impact on the United States as a whole. It politically affected both the North and the South. The overall destruction of the war lead to the reconstruction of the nation, mainly the south in particular. The government implemented federal authority which they called Martial Law. All of this leading to the advancements for women and minorities who were previously perceived as lower than white males.
The North was clearly dominated by the Republican Party with the exception of Johnson when Lincoln was assassinated. Their views most certainly were in contrast to those of the South which was one of the real causes of the war. So as the war progressed on the party made many moves in the advancement of the country. Countless acts were passed, the most notable being the Homestead Act of 1862. Advancements in the transcontinental railroad were arising and its completion was coming soon. The high tariffs placed on goods helped stabilize the Northern economy in industry.
As for Lincoln's role in the war, one of his most strategic political and militaristic move came in the form of the Emancipation Proclamation. He knew that European involvement in the war was on the horizon so he had to devise a way of giving them a war the European countries would want no part in. Instead of the Confederates fighting for independence, Lincoln portrayed them as fighting for slavery. He did in fact feel as though slavery should be abolished but knew that this document wasn't what was to do it. After the declaration of the document on January 1, 1863 it changed the war in favor of the Union. Not a single slave was freed through the document but the European involvement that was so prevalent faded to almost nothing.
When the bloodiest war in American history came to a close, roughly 620,000 were dead. It left the divided US around 15 billion dollars in debt and left cities like Richmond Virginia, Atlanta Georgia, and Columbia South Carolina in shambles.