Ending in 1865, the American Civil War was the deadliest conflict in United States history. The war divided families and friends, it challenged the traditional power structure in America, and it ended with some of the most consequential changes in American history, chief among these the end of slavery.

Throughout the war, Abraham Lincoln was one of the most hated men in the country; simultaneously, he was one of the most admired, especially as the war neared its end. Everything about Lincoln’s story suggested a sort of larger than life, mythological character. He was born into poverty. He was self-educated. He was a tall, imposing, brooding-looking man. He was eloquent and gave speeches steeped in religious imagery and poetic flare. And he endured throughout the most difficult presidency in the history of the country.

Walt Whitman loved Lincoln. He thought the President was a romantic and spiritual soul, akin to how Whitman viewed himself. He felt a kindred bond to the President, and Lincoln’s death severely affected him.

“O Captain!” is an example of a poem that arrived at the right time. As the country mourned its fallen leader at the conclusion of the war, poems like Whitman’s fueled the public’s grief and immediately helped mythologize the late President.