Reasons the Emancipation Proclamation was Important
The Limitations of the Document
Why is the Emancipation Proclamation important to understanding US history? The most obvious answer to this question is actually incorrect.
The proclamation did not free all of the slaves in the US, nor did it truly abolish slavery. In fact, it only applied to states that had already seceded from the Union and had not yet been returned to Union control. That meant that the Border states, as well as the Confederate states that the North had already brought back into their control, were not affected by the proclamation at all. The only slaves that were theoretically affected by the Proclamation were those that were in Confederate-controlled states - which were not under Lincoln's jurisdiction at the time. In other words, the slaves were not yet free until the Union won the war.
Lincoln's Secretary of State William Seward noted this irony when he said, "We show our sympathy with slavery by emancipating slaves where we cannot reach them and holding them in bondage where we can set them free."
How It Changed the War
So then what was the purpose of the Emancipation Proclamation? How did it change the course of the Civil War? In fact, the Proclamation was more of a symbolic statement than anything else. It didn't change the existence of slavery, but it did change the meaning of the Civil War. Originally, the war was merely a fight in which the North was trying to preserve the Union by reuniting the North and South. The Proclamation changed the war into a war on slavery. After the Proclamation, each Union victory was a victory for those who opposed slavery. It gave slaves who were fighting for their freedom a reason to hope again, and it gave those who supported the Union moral support to depend on.
On the heels of the Proclamation, Lincoln proposed that part of the Republican Party's platform in 1864 should address a possible constitutional amendment that would abolish slavery. This suggestion eventually led to the 13th Amendment, which made slavery illegal.
Other Effects of the Proclamation
There is one other, less blatant, reason to answer the question "Why is the Emancipation Proclamation Important?" In the Proclamation, Lincoln declared that freed slaves could fight for the Union. Additional soldiers were desperately needed at that point, so the Union was utilizing the previous unelibible men to assist in conserving the country. By the war's end, close to 200,000 black soldiers and sailors had fought on the Union's side.
In summary, why was the Emancipation Proclamation written? It was written to show that the Civil War was no longer just about a divided nation, but about stemming the tide of slavery. The Proclamation was used to increase morale and the number or soldiers to win the war. Although it did not accomplish anything tangible (other than adding to the Union army), it gave hope to those who wished and fought to abolish slavery.
Edsitement. "The Emancipation Proclamation: Freedom's First Steps." http://edsitement.neh.gov/lesson-plan/emancipation-proclamation-freedoms-first-steps
National Archives and Records Administration. "The Emancipation Proclamation." http://www.archives.gov/exhibits/featured_documents/emancipation_proclamation
Picture of Abraham Lincoln and the Emancipation Proclamation by Perine & Giles [Public domain], via Wikimedia Commons
Picture of Emancipation Procamation by Abraham Lincoln, digital reproduction by George Chriss (GChriss). With prior publication, the Emancipation Proclamation became effective 1-January-1863. (Own work) [Public domain], via Wikimedia Commons