One of the interesting effects was a surge in emigration from Germany and Hungary to the United States. Many of these men and women would subsequently play key roles in the American Civil War on the northern side, as they were predominantly progressives and thus strongly anti-slavery. Hundreds of thousands of German and central European immigrants filled Union divisions and corps during the war and inspired much of the movement toward emancipation during the early war, when much of the rest of the country was focused simply on keeping the Union together.