Answer:
It was written in memory of someone who died.
Step-by-step explanation:
The poem "O Captain! My Captain!" has been written by Walt Whitman. He has written the poem after the assassination of the president of America, Abraham Lincoln. It is because of this reason that it is said to be an elegy. An elegy is a poem that is written about the death of a person to remember him and to mourn at his death.